OF POWER FAIL.URES ‘-
ort
of
the Commission
A Report to the President
by the
Federal Power Commission
July
1967
PREVENTION
OF POWER FAILURES
An Analysis and Recommendations
Pertaining to the Northeast Failure
and the
Reliability of U.S. Power Systems
I
I
Volume I-Report of the Commission
A Report to the President
by the
cu ,s ,A Federal Power Commission ,
II
July 1967
For sale by the Superintendent of Documents, U.8. Government Printing Office
Washington, D.C. 20402 - Pnce II.60
FEDERAL POWER COMMISSION
WASHINGTON
July 19, 1967
Dear Mr. President:
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We are pleased to transmit our final report on
the Northeast power failure of November 9-10,
1965, and our recommendations for enhancing
power system reliability in the Northeast and
elsewhere in the Nation. This report is in
response to your memorandum of November 9,
1965, and the strong interest evidenced by
Congress and the public at large in seeking
the causes of the failure and the steps necessary to prevent recurrences. It supplements
our December 6, 1965 analysis of the power
failure and our interim reports of April and
November, 1966.
At the time of the cascading failure, questions
were raised as to whether a fundamental error
had been made in permitting utility systems to
be so dependent on other systems that the failure
of one could jeopardize great areas of the country
and conceivably the entire Nation. The various
segments of the industry, responsible observers
including scientists, technicians, and academicians
and interested governmental agencies are in agreement that the concept of coordinated efforts is
not only a very successful means of achieving
lower cost power, but actually enhances the
reliability of participating systems. The key
lesson of the Northeast failure and the subsequent
cascading outages, we believe, is that these interconnections and the coordination of diverse systems
must be strong in order to be effective.
I
Since November 9, 1965, many of the more easily
achieved improvements in emergency equipment,
communications and controls have been initiated
I
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The President
The White House
Washington, D. C.
20500
The President
-2.
or completed in the Northeast and throughout the
Nation. These steps will be helpful in avoiding
a collapse in power supply. Should failures occur,
however, those systems which have improved their
equipment will be able to restore power more
quickly. Attention has also been focused upon
providing emergency power for essential services
during outages of commercial power. But as
constructive and as encouraging as these improvements are, we believe the prevention of crippling
power failures requires much more,
The Nation's electric power industry consisting of
over 3500 utilities of diverse size and ownership-investor-owned companies, municipal and statesponsored systems, rural electric cooperatives,
and federal systems-- generally has a superb record
of supplying low-cost power on a reliable basis.
We are, however, so dependent on continuouselectric
power in our urbanized and industrialized society
that additional efforts must be made to reduce even
further the likelihood of potentially hazardous
area-wide power failures. Our studies, in which
experts from every segment of the industry assisted,
convince us that the prevention of major cascading
failures of the type which hit the Northeast in
1965 and very recently in eastern Pennsylvania,
New Jersey and the Delmarva peninsula, requires
expanded coordination among all utilities on a
region-wide basis and a substantial strengthening
of transmission systems. We believe implementation
of the recommendations in this report--and, as noted
above, many are either totally or partially in force
today--will substantially assist the industry to
achieve these objectives.
As you are aware, the Commission earlier this month
submitted to the Congress a proposed "Electric
Power Reliability Act of 1967." That bill would
authorize the FPC to play a role in accomplishing
a number of the recommendations contained in this
report and, in large measure, the bill rests upon
the same studies and analyses which underlie this
final report on the Northeast power failure of
November 1965.
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The Senate Commerce Committee and the House
Interstate and Foreign Commerce Committee have
demonstrated deep interest in the general problem
of reliability of electric service and, accordingly, we are sending copies of our report to
the members of those Committees. Additionally,
because the report contains some information and
suggestions applicable to state and local governments, copies are being sent to the governor of
each state.
We are grateful for your personal and continuing
concern for power reliability, evidenced in so
many ways including, of course, references in
the State of the Union message and in your Special
Message to Congress on Consumer Problems. We are
confident that our recommendations will result in
more dependable electric service to the Nation's
power consumers --a goal that you have articulated,
that the Congress has supported, that this Commission and state regulatory bodies must support,
that the industry has traditionally given the
highest priority and that the public has a right
to expect.
Respectfully,
bee C. White, Chairman
Commissioner
Charles R. Ross, Commissioner
CONTENTS
PREFACE.......................................................
CHAPTER l-PREVENTION OF POWER FAILURES-HIGHLIGHTS
OF THE REPORT................................
CHAPTER P-THE NORTHEAST FAILURE-REMEDIAL ACTIONS
AND REQUIREMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circumstances of the Failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Impact on the Public . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Status of Improvements in the Northeast. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Equipment Additions and Modifications. . . . . . . . . . . . . . . . . . . . . . . . .
Spinning Reserve Practices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Provisions for Load Shedding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Service to New York City. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power for New York Subway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ServicetoBoston . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Studies of Northeast Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Projections of Development by Northeast Utilities. . . . . . . . . . . . . . . .
Need for Further Study. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Northeast Power Coordinating Council. ............... 1 . . . . . . . .
CHAPTER 3-POWER INTERRUPTIONS AND INTERRUPTIONS
AVOIDED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power Interruptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. PJM Power Failure, June 5, 1967 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Reporting Power Failures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Summary of Power Interruptions 1954-1966 . . . . . . . . . . . . . . . . . . . . . .
Interruptions Avoided . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHAPTER 4-COMPOSITION, INTERCONNECTION, AND COORDINATION OF ELECTRIC SYSTEMS. . . . . . . . . .
Composition of the Industry . . . . . . . . . . . . . . . . . . . .
Interconnection of Utilities. . . . . . . . . . . . . . . . . . . . .
Coordinated Planning and Operation . . . . . . . . . . . .
Benefits of Coordination. . . . . . . . . . . . . . . . . . . . . . .
The PJM Interconnection . . . . . . . . . . . . . . . . . . . . . .
Other Forms of Coordination . . . . . . . . . . . . . . . . . . .
Areas for Improving Coordinating Organizations. .
Continuing Problems. . . . . . . . . . . . . . . . . . . . . . . . . .
Conclusion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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VI11
C H A P T E R 5 - K E Y - E L E M E N T S F O R R E L I A B I L I T Y I N THE
PLANNING AND OPERATION OF INTERCONNECTED POWER SYSTEMS . . . . . . . . . . . . . . . . . . . . . .
We
Key Elements in Reliability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Load Projections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lead Time for Planning and Construction . . . . . . . . . . . . . . . . . . . . . . . . . . .
System Generating Reserve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Importance of Transmission in Reliability. . . . . . . . . . . . . . . . . . . . . . . . . . .
Regional and Interregional Coordination . . . . . . .1 . . . . . . . . . . . . . . . . . . . .
Network Stability Analyses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Direct Current Interconnections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Problems of Separated Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LoadShedding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Relay and Control Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Dependable Communications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Computer Application in Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Restoration of System Services. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Criteria and Standards for Reliability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OperationGuides . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CentralStudyGroup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
41
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45
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46
48
50
51
52
53
54
55
55
56
56
41
CHAPTER &-THE ROLE OF TRANSMISSION IN RELIABILITY. .
57
Transmission Objectives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bases for Appraisal of Transmission Needs. . . . . . . . . . . . . . . . . . . . . . . . . . .
Possible Pattern of Needed Transmission. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cost of EHV .Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Economic and Social Justification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Alternative Considerations for Achieving Reliability. . . . . . . . . . . . . . . . . .
Regional and Inter-regional Planning and Cost Sharing. . . . . . . . . . . . . . . .
57
58
58
62
63
64
64
CHAPTER ‘I-OTHER RELIABILITY CONSIDERATIONS. . . . . . . . . .
67
Defense Implications of Power Failures. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Defense Impacts of the Power Interruption . . . . . . . . . . . . . . . . . . . . . . .
Power Systems and Sabotage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Vulnerability of Power Systems to Nuclear Attack . . . . . . . . . . . . . . . . .
Attributes of Power Systems in Surviving Severe Damage. . . . . . . . . .
Fallout Shelters and Power Requirements. . . . . . . . . . . . . . . . . . . . . . . .
Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Emergency Power for Essential Public Services. . . . . . . . . . . . . . . . . . . . . . .
Equipment Reliability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Research and Development Needs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Capacity Requirements in Relation to Manufacturing Capability. . . . . . .
Preservation of Aesthetic Values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Technical Talent for the Industry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Observations on Power Systems of Other Countries. . . . . . . . . . . . . . . . . . .
International Interconnections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interconnected Operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Examples of Particular Systems and Practices. . . . . . . . . . . . . . . . . . . . .
PowerFailures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
International Technical Exchanges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Comparability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
67
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71
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2-PC
CHAPTER 8-THE COMMISSION’S RESPONSIBILITIES AND
ACTIVITIES TO IMPROVE COORDINATION AND
RELIABILITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
The Commission’s Responsibilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
FPC Activities in Coordination. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Further Commission Assistance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CHAPTER 9-CONCLUSIONS AND RECOMMENDATIONS . . . . . . . .
Formation of Coordinating Organizations. . . . . . . . . . . . . . . . . . . . . . . . . . .
Interconnected System Planning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Interconnected System Operating Practices. . . . . . . . . . . . . . . . . . . . . . . . . .
Interconnected System Maintenance Practices. . . . . . . . . . . . . . . . . . . . . . .
Criteria and Standards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Defense and Emergency Preparedness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Manufacturing and Testing Responsibilities. . . . . . . . . . . . . . . . . . . . . . . . . .
Increased Need for Technical Proficiency. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Power System Practices in Other Countries. . . . . . . . . . . . . . . . . . . . . . . . . .
ACKNOWLEDGMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Surveys of the Reliability Characteristics of U.S. Power
Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix A-General
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Criteria for General Surveys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GeneralSurveys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix B-Mod@ations to Northeast Power Systems Since November 9, 1965. .
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Relaying . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Emergency Power at Generating Stations . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Communications, Instrumentation, and Data Transmission. . . . . . . . . . . .
Spinning Reserves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LoadReduction........: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix C-Major Coordinating Organ&ations. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mechanisms for Coordination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Members of Major Formal Power Pools. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Members of Major Power Planning Groups . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix D-Impact of Power Failures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
AgencyActions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Legislative Proposals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Appendix E-Summary of Larger Power Interruptions 19561967. . . . . . . . . . . . . .
Volume II-Report of the Advisory Committee on Reliability of Electric Bulk Power Supply, Separate Volume.
Volume III-Studies of the Task Groups on the Northeast Power Interruption, Separate Volume.
i.
TABLES
l-Major Power Failures Which Have Occurred Subsequent to the Northeast Failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-Power Service Interruptions Reported ‘in Accordance with FPC Order
No. 331 through June 12, 196?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-Regional Distribution of Electric Utilities-1965, By Function. . . . . . . . . .
2
4---Regional Distribution of Electric Utilities-1965, By Size of. Energy
Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .‘. . . . . . . . . . . . . . . . . . . .
5-Statistics on Electric Po.wer Systems in Other Countries . . . . . . . . . . . . . . . .
A-l-Stability Studies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A-2-Comparison by Regions of Number of Systems Using Automatic
Emergency Load Reduction Programs. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A-S-Comparison by Regions of Automatic Emergency Load Reduction
Programs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A-+--Emergency Load Reduction Program, by Regions. . . . . . . . . . . . . . . . . .
A-5-Load & Generation Emergency Dropping Practices, by Regions. . . . . .
A-6-Spinning Reserve Practices, by Regions. . . . . . . . . . . . . . . . . . . . . . . . . . .
A-7-Means of Obtaining Emergency Startup Power, by Regions . . . . . . . . . .
A-8-Practices & Plans for Use of Digital Computers, by Regions. . . . . . . . . .
B-l-Emergency Power Supplies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B-2-Communication, Instrumentation, and Data Transmission. . . . . . . . . . .
B-S-Spinning Reserves-Northeast Power Systems. . . . . . . . . . . . . . . . . . . . . .
B-+--Load Reduction Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D-l-Selected Essential Services Requiring Emergency Electric Power. . . . . .
D-P-Port of New York Authority Emergency Electric Power Equipment. . . .
D-J-State Codes and Regulations for Emergency Power. . . . . . . . . . . . . . . . .
E- 1-RbumC of Power Interruptions 1954-l 966. . . . . . . . . . . . . . . . . . . . . . . .
23*-a
32
76
102
122
122
123
129
132
148
147
156
160
162
163
173
179
186
194
FIGURES
I
l-Power Failure in the Northeast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-Service Area Separations Northeastern Power Failure, November 9,
1965 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3*-15,000 kw Gas Turbine Generating Unit for Peaking and Station
Startup-Long Island Lighting Company’s Port Jefferson Station. . . .
4*-Emergency Standby Power-608 Kw Diesel Set at Consolidated
Edison Company’s Hudson Avenue Generating Station. . . . . . . . . . . . . .
5-Major Transmission Lines and Generating Stations. . . . . . . . . . . . . . . . . . .
GMember Systems of Northeast Power Coordinating Council. . . . . . . . . . . .
7-PJM Area Power Failure-June 5, 1967 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8-PJM Transmission Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9-Service Areas of Electric Utility Industry. . . . . . . . . . . . . . . . . . . . . . . . . . . .
lo-National Power Survey Regions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 l-Growth of Interconnected Systems Operating in Parallel. . . . . . . . . . . . . .
12-Major PowerPools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13-Principal Power Planning Groups in U.S., March 1967. . . . . . . . . . . . . . .
14-Electric Energy Requirements 1960-l 980. . . . . . . . . . . . . . : . . . . . . . . . . . .
15-Response of Interconnected Network Power Flow to Outage of TVA
Paradise Steam Plant. . . . . . . . . . . . . . . . :. . . . . . . . . . . . . . . . . . . . . . . . . .
16*-Model of North Terminal of Pacific Northwest-Southwest Direct
Current Intertie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
17-Generation and Frequency Variations November 9, 1965. . . . . . . . . . . . .
18-Automatic Load Shedding. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
19*--ProtectiveRelay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PO-Energy Control Center fo Consolidated Edison Co. in New York City. . . .
Pl-Possible Pattern of Transmission by 1975. . . . . . . . . . . . . . . . . . . . . . . . . . .
PP-Projected Investment in EHV transmission . . . . . . . . . . . . . . . . . . . . . . . . . .
* Photograph.
7
8
9
13
17
18
24
25
33
34
35
36
38
42
47
48
49
51
52
53
60
63
SC
24-Ste
25-PO1
26Tn
27-Em
D-1-c
E-l-PC
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Page
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23*-500 kv Transmission Tower on BPA Portion of Pacific NorthwestSouthwest Intertie . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B&-Steam Turbine Generators. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25-Power Transformers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I . .
26-Transmission Lines in Western Europe. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
27-European Power Pools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D-l-Questionnaire Used by Business & Defense Services Administration. . .
E-l-Power Interruptions, 19541966. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
32
76
i. 102
122
E
122
123
: 129
f; 132
, 140
e 147
156
i 160
; 162
163
173
179
i 186
L 194
* Photograph.
1,:
7
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34
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; 36
38
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4
7
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1 48
49
/ 51
52
53
60
63
65
73
73
77
78
176
197
PREFACE
This report summarizes more than a year of intensive investigation following the Northeast power failure
of November 9, 1965. Many utilities, agencies of Federal, State, and local governments, and committees of
Congress have joined in reviewing the Northeast failure and its significance in relation to the reliability of
the Nation’s electric power supply. The area in which the failure occurred has been studied intensively and
utilities in every part of the Nation have been reviewing practices in power system planning and operation in
the light of the lessons revealed by the Northeast failure.
The report summarizes the actions taken by utilities in the Northeast and elsewhere in the Nation and
the need for further improvements. It reviews the history of major power failures, analyzes the elements which
compose a reliable generation and transmission system and their functions, discusses the necessity for reliability
and its value, projects an accelerated scale of development for EHV transmission lines, and discusses important
elements in coordinated power system planning, including effective regional organizations, lead time for
planning and construction, sound load projections, environmental effects of system facilities and the recruitment of technical talent to meet the unparalleled challenges of modern power system technology. The report
discusses practices in other countries having well-developed power systems, and considers the relation between
cascading failures and the survivability of United States power systems under enemy attack.
The supply of bulk electric power is considered to include the generation of electric power and its
transmission at high voltage to major substations near load centers. Reliability in the distribution of power
from substations to customers is not included.
As used in this report, the term “reliability” means the ability of a utility system or group of systems to
maintain the supply of power. Reliability is gauged by the infrequency of interruption, the size of the area
affected, and the quickness with which the bulk power supply is restored if interrupted. For many reasons it
is not possible to provide an infallible source of power, but the probability of interruption and the area affected
can be greatly minimized by following sound practices in planning and operating power systems.
The Commission’s report to the President, December 6, 1965, on the Northeast Power Failure l contains
a detailed account of the cause and the sequential events which resulted in the widespread separation and
collapse of power systems on November 9, 1965, and presents recommendations for preventing recurrence of
major failures. Although not republished as a part of this report, it is a principal reference.
The report herewith is in three volumes. Volume I is the report of the Commission. Staff work for the
report was carried out under the direction of F. Stewart Brown, the Commission’s Chief Engineer and Chief
Df the Bureau of Power.
Volume II is the report of the Commission’s Advisory Committee on the Reliability of Electric Bulk
Power Supply. This Committee was established by the Commission by Order dated February 9, 1965, “to
review and investigate the problems in assuring the reliable supply of bulk power” and to “recommend general
criteria and guidelines for system planning and operation and maintenance of facilites to assure the reliability
d bulk power supply * * +.”
Volume III summarizes the Task Group studies performed under the general guidance of the Federal
Power Commission and its Advisory Panel for the Northeast Power Interruption. The studies include an
examination of the strength of the Northeast transmission network under assumed severe disturbances, an
appraisal of needed network additions, and a detailed analysis of the collapse in power supply in the eastern
New York and New England “island’ area which occurred progressively over a period as long as 12 minutes.
The Commission is greatly indebted to many persons and organizations for their cooperative assistance
in the studies and assembly of information on which the report is based. Acknowledgment of those who have
1 “Northeast Power Failure November 9 and 10, 1965-A report to the President by the Federal Power Commission,
December 6, 1965”-Superintendent of Documents, U.S. Government Printing Ofice, Washington, D.C.-Price $1.00.
been of principal help to the Commission and its staff are included in the separate volumes of the reporf
as follows:
. Members of the Commission’s Executive Advisory Committee and of the six Regional Advise
Committees, in “Acknowledgments” following Chapter 9 of this Volume.
. Members of the Commission’s Advisory Committee on Reliability of Electric Bulk Power supp
in Volume II.
. Members of the Commission’s Advisory Panel on the Northeast Power Interruption, and members
Task Groups associated with the Panel, in Volume III.
. Those who participated with the Commission in the immediate weeks following the Northeast pow
failure are acknowledged in the Commission’s report to the President, December 6, 1965, on tht
The masz
Northeast Power Failure.
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CHAPTER 1
I
ortheast power
#, 1965. on the
THE PREVENTION OF POWER FAILURES-HIGHLIGHTS OF THE REPORT
’
The massive power failure of November 9, 1965,
which cascaded across the northeastern United
States and Ontario, Canada, affecting 30 million
i people, touched off the most intensive examination
of power system planning and operation in the
/ 85-year history of the electric power industry. All
/ of the nation’s utilities have been challenged to con! sider whether similar failures could occur in their
1 areas. If so, what steps should be taken to prevent
them? If they should occur, could power be restored
quickly? Such questions have demanded a searching review of the fundamentals of interconnected
1 utility operation. Rigorous self-analyses have been
made by many utilities and the industry has responded to the Commission’s review with coopera’ tion and candor.
I As our previous reports 1 indicated, the cascading
: of the failure of November 9 occurred because the
transmission network in the Northeast and the
transmission connections to the south and west were
too weak to withstand the massive power surge. The
i network was not planned to withstand such a surge,
, and under the impact, it became unstable and ceased
\ to function as an integrated whole. Transmission
ties separated, isolating the Northeast from the rest
I of the country and subdividing the Northeast into
several electrical “islands”. In most of the island
areas, loads were greater than generation-so much
so that the automatic response of the generators
I could not restore equilibrium. Utility systems in
t these areas were not equipped with automatic
ontrols to drop loads temporarily before rebuild‘ng to full load. The numerous utility control rooms
En the Northeast were unable to exchange informaItion in time to take such emergency actions as were
jopen to them. As a consequence, power generation
jceased.
Because many of the utility systems lacked adeuate‘startup resources and procedures, restoration
f service was delayed for several hours and in parts
1 FPC Report to the President on December 6, 1965,
nd Interim Reports in April 1966 and November 1966.
of New York City for periods up to 13 hours. While
much public loss and inconvenience were caused
by the outage, general tragedy was averted by the
ability of radiostations having emergency power to
inform the public, by the good sense of hundreds of
thousands of people and by fortunate weather conditions.
The initial reaction to the Northeast failure was
one of general disbelief that such an incident could
happen. The outstanding record of service of electric utilities in the United States certainly had given
little suggestion that a widespread failure of this
magnitude could occur. The sequence of difficulties
which ensued, exposing the types of deficiencies
enumerated herein, appeared contrary to the performance of utilities in meeting hundreds of emergencies that have arisen year after year on power
systems everywhere in the United States.
In perspective, it should be recognized that the
electric utility industry is confronted with the most
difficult challenge of any of the public utility services in assuring the continuity of supply. There are
no ways to hold power demands in waiting, no electric storage pools and no ways of providing partial
service to overcome unexpected peak demands or
suddenly to fill gaps in equipment failures. These
must be met by more difficult means and peak demands must be served instantaneously and in full.
Electric power generating machines throughout
the nation must work together in split-second
synchronism.
The industry responds to emergencies with alacrity and dedication. The industry has good reason
for pride in its overall record of service, in its
growth achievements, and in its discharge of a vital
public service responsibility that must be virtually
unfailing. The problems before us do not stem from
any lack of desire of any individual utility to do its
best. They are generated in part by the dynamic
growth of the industry and the difficulties of keeping
pace in all respects with these demands. They con1
tern primarily the requirements for greater COordination among electric utility systems.
Although some improvements undertaken by the
utilities since the 1965 failure have not been completed because demands for equipment, such as
emergency power units, temporarily exceeded manufacturers’ capabilities, the industry has gone far to
protect its own equipment from damage, to be prepared for speedier restoration of service, to improve
communications to and from the various utility
control rooms, and to make plans for temporary
dropping of less essential loads (load shedding) to
avoid a complete power failure in case of similar
crises. Also, utilities in the Northeast and in many
other locations throughout the nation have proceeded independently or in cooperation with the
Commission as requested in numerous studies and
surveys relating to reliability.
The critical remaining needs which many utilities are striving to meet are to develop mechanisms
for effective coordinated planning, design, construction and operation of generation and transmission
facilities. The challenges here are as much institutional as technical: there are hundreds of large and
small utilities, privately, publicly, cooperatively and
federally owned. The technology of reliability, however, ignores ownership and calls for a high degree
of coordination in planning and functional cooperation by the diverse managements in carrying out
their bulk power supply responsibilities.
Bulk power systems consist of generating and
transmission facilities. The individual pieces of
equipment are fallible and components will be
forced out of service from time to time. Major
equipment outages, however, should not result in
service interruptions if the many generating plants
of a large group of systems are joined by strong transmission lines which enable each generating unit to
instantly make a contribution. These small individual contributions can, in the aggregate, offset the
outage. Adequate generating reserves must be at
hand to take the place of failed equipment until it
is repaired, but without strong interlocking transmission systems, even large and costly amounts of
reserve may not prevent interruptions. Transmission lines designed with adequate reserve capacity,
which is what we mean by strong ties, can sustain
the impact of sudden changes in generation or load,
such as the power surge of November 9, without becoming unstable and opening. Well-planned systems with adequate automatic controls and interconnected over a wide area, result in a high quality
2
of electric service with little fluctuation in system frequency or voltages-a characteristic important to
many industrial processes.
Beginning with various local transmission links
among utilities prior to World War II, interconnection has continued to progress, largely through
the voluntary efforts of utilities, to the present pattern in which the transmission systems of all principal utilities have become interwoven into a continuous transmission network which nearly blankets
the United States and includes part of Canada.
However, many of the links are weak, and additional ties are needed.
The underlying theme of the report of the Commission’s Advisory Committee on the Reliability of
Electric Bulk Power Supply (Volume II of this report) is that the transmission capacity of the interconnected network must be adequate. The report
states :
Transmission must be recognized as the principal
medium for achieving reliability, both within a system and
through coordination among systems. It is the cohesive
force which ties together power systems. Cascading power
failures are usually the result of insufficient capability
within the transmission links of a system or group of systems to withstand the sudden demands placed upon them
by reason of disturbances arising within or outside the
system.
Our studies bear out the views of the Committee.
The Northeast power failure clearly revealed that
systems and interties between systems must have
ample reserve transmission capacity to supply
power demands much in excess of normal load
requirements. Seventeen of the 20 major failures
which have occurred since November 9, 1965, have
also been cascading failures, each the result of
interconnections which were too weak to cope with
the particular system disturbance. Progress toward
stronger transmission systems must be accelerated
if all utilities in the United States are to be able
both to provide and receive strong emergency
support.
If EHV transmission lines are built by 1975 to
the level of development suggested in this report,
a rough estimate of the added investment is $8
billion, which is about 12.5 percent of the anticipated expenditures for all power facilities over the
same period. This amount is about $3 billion more
than utilities apparently contemplate spending, assuming reasonable extrapolation of recently announced planned rates for EHV construction. The
annual cost of a $3 billion increment of investment, which might be considered to represent the
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principal cost of obtaining greater reliability, would
be less than 2 percent of the total cost of supplying electric power in 1975. The added investment
in coordination and transmission might also accelerate the achievement of the economic gains projected in the Commission’s National Power Survey published in December 1964.
Effective coordination of bulk power facilities
cannot be achieved by mere interconnection. It
must encompass mutual review of load projections
by utilities in each region, coordination in construction proposals, and agreement upon operating practices and safeguards.
Coordination and interconnection can produce
significant benefits in addition to increased reliability. When adequate networks are fully developed,
the economy of bulk power supply will be enhanced through regional and interregional exchanges of capacity and energy, sharing of spinning and standby reserves, and the transfer of
emergency power supplies for meeting unusual
weather conditions and other contingencies. Economy and reliability are closely associated objectives
in the supply of electric bulk power, but reliability
must have priority if any conflict occurs.
The early establishment of strong organizations
for regional planning and operation is essential to
the orderly growth of the electric utility industry.
The Advisory Committee on Reliability recommends:
the establishment of effective organizations and procedures
to implement the necessary coordination among planning,
engineering and operating personnel of the participating
utilities, with assigned responsibility to review, adjudge,
report upon, and effectuate utility plans and practices
within the area affecting bulk power system reliability.
A regional coordinating organization was created
by electric utilities in the Northeast early in 1966
and in the East Central area in 1967. Although still
engaged with some of the problems of organizing
and programming, these councils are directing
useful efforts in the analysis of bulk power generation and transmission to improve reliability
through coordination.
Fears are frequently expressed that coordinating
mechanisms would encroach upon prerogatives of
individual management. Such concerns, we believe,
fail to take into account that full management
responsibility can be achieved only by joining in
planning which extends beyond the boundaries of
a corporate or other entity, an area or even a region.
To the extent there is such encroachment, we be%7-781 O - 6 7 - 2
lieve it must be balanced against the legitimate
system, area, regional and national interest in reliable service. No management can avoid its share
of the responsibility for building adequate interconnected transmission systems.
Coordinated planning and operation must not
only be extended more broadly among the 437
investor-owned utilities which furnish nearly 80
percent of total electric needs, but must bridge as
well the differences among the four segments composing the industry’s.total structure. Reliability and
economy should be available to all users of bulk
electric power, regardless of the nature of the
system serving them. At the same time these users
must contribute their proper share of the cost.
Useful mechanisms have evolved for coordinating the planning and operation of systems in some
areas. Others have not matured to levels of optimum effectiveness. Some are too limited in purpose to serve adequately as instruments of coordination. We are mindful, however, of the progress
achieved and the opportunity for expanding the
scope and usefulness of these existing mechanisms.
We do not suggest setting them aside, but rather
building upon them as steps toward greater accom.
plishments.
In accordance with section 202 (a) of the Federal Power Act, the Commission has endeavored to
promote and encourage the interconnection of
systems for the enhancement of both economy and
reliability of electric power supply. We beheve the
industry has been stimulated by the efforts of the
Commission “to promote and encourage voluntary
interconnection.” Accelerated progress, however,
will be needed to satisfy the demands in both
quantity and quality of service over the next
decade.
Substantial economic gains can be achieved
through coordinated planning and operation spanning a large area or region.2 Close coordination
within regions is the most practical approach and
the foundation for achieving bulk power supply
reliability for the nation. However, interregional
coordination is a further necessary step. The Advisory Committee on Reliability recognizes this need
and suggests :
The establishment of a council on power system coordination made up of top-level representatives from each of
*In the Commission’s National Power Survey, the 48
contiguous states are grouped into 16 areas and 8 regions.
In the current updating of the National Power Survey, six
regions have been delineated.
3
the nation’s area OF regional coordination groups. The
purposes of such a body would be primarily to exchange
and disseminate information on regional coordination
practices to all of the regional organizations, to communicate to the public and regulatory and governmental authorities information on coordination, and to review,
discuss and resolve matters affecting interregional coordination.
.
We concur in the Committee’s view.
Also we believe there would be much merit in
coordination of investigative efforts by the
industry to meet some of the challenging opportunities for improving power system facilities and
operations.
Electric power use by 1985 is expected to be more
than three times that of today. Supplying these demands economically calls for increasingly larger
generating unit and plant capacities and correspondingly stronger transmission systems. All, of
course, must be in keeping with the density of the
load and other factors which may be of significance
in a particular area. Fortunately, the technology is
now available or can reasonably be anticipated,
which will permit such increases with continuing
gains in both economy and reliability.
. We are concerned that delays from many causes
are adding years, not months, to planning and construction schedules for major generation and transmission facilities. The nation may be confronted
with a serious impairment in the sufficiency and
dependability of its electric supply if prompt recognition is not given to these potential delays. Unexpected demands, particularly those influenced by
prolonged summer heat storms, have already encroached on normal margins of reserve generating
capacity in some areas. A few areas are faced with a
possible curtailment of service in 1967, such as happened in the St. Louis area last summer, if extreme
weather occurs, particularly if one or more large
generating units experience a,forced outage during
the peak period. Sufficient generation is at hand in
neighboring systems to overcome the deficiency, but
transmission strength is insufficient in many cases
to move all available surplus within safe line loading
limits. Such limitations in generating capacity and
the inability to utilize all available generating resources in neighboring areas to benefit marginal situations because transmission is inadequate, are of
serious concern.
Our emphasis on accelerating the construction of
high capacity, high voltage lines does not indicate
lack of concern for the appearance and location of
power system structures. We believe that much
further
greater attention must be given to the aesthetics of
public service facilities, and that the public should
be brought into the planning process as early as possible. The present severe economic and technical
limitations on placing extra-high-voltage transmission lines underground demand an intensification of
research in this area. In addition, major efforts are
needed to improve overhead transmission line appearance, to select inconspicuous routings, and to
make the best use of existing rights-of-way.
We recognize that the location of generating stations affects the pattern of transmission. To the
extent that large generating plants are placed closer
to load centers, the average distance for moving
bulk power supplies can be reduced. However, the
requirements for cooling water, the difficulties of
acquiring suitable close-in sites, the increased seriousness of air pollution in densely populated areas,
and the favorable economics of some mine-mouth
locations will tend to limit the number of plants
that can be placed at load centers. Thus the supply
of bulk power to many centers will still require
major transmission. More fundamentally, these considerations do not lessen the need for an effective
overlay of high voltage lines to improve the reliability of bulk power supply.
Achieving adequate reliability throughout the nation will engage not months, but years of concerted
planning and construction. We believe the 12 recommendations which follow go to the heart of
the problem. They are drawn from the recommendations, 34 in all, which are set forth in detail in
chapter 9. The supplemental recommendations concern numerous improvements in the planning,
operating, and maintenance of interconnected systems, defense emergency preparedness, responsibility in the manufacturing and testing of equipment,
and the challenge to technical talent.
In summary we conclude and recommend, principally, that :
1. To the extent they do not now exist, strong
regional organizations be established throughout the nation, for coordinating the planning, construction, operation and maintenance of individual bulk power supply
systems; and that representation of systems be
by groups, where feasible, to facilitate
progressive improvements in coordination.
2. A council on power coordination be established, made up of representatives from each
of the nation’s regional coordinating organizations to exchange and disseminate informa-
B
/
i
r
3.
4.
5.
6.
7.
c
recof
rinI0%
ugh$ lantePlY
F
ms be
litate
31:
!stabeach
gani‘ma-
tion on regional coordinating practices to all
of the regional organizations, and to review,
discuss and assist in resolving matters affecting interregional coordination.
A central study group or committee be established to coordinate industry efforts in investigating some of the more challenging
problems of interconnected system development.
Early action be taken to strengthen transmission systems serving the Northeast.
Transmission facilities be critically reviewed
throughout the nation, and planning and
construction of needed additions be accelerated on schedules which will provide ample
transmission capacity to meet a broad range
of potential needs for both reliability and
economy as they occur.
In estimating future loads, full attention
be given to economic trends, potential
weather extremes, and growth in special
uses of electricity in each load area.
Utilities solicit the full participation of interested parties at an early date in the resolution of problems relating to the location and
environmental effects of new facilities.
8. Utilities intensify the pursuit of all opportunities to expand the effective use of computers
in power system planning and operation.
9. Coordinated programs of automatic load
shedding be established and maintained in
areas not so equipped, to prevent the total
loss of power in an area that has been separated from the main network and is deficient
in generation. Load shedding should be regarded as an insurance program and should
not be used as a substitute for adequate system design.
10. Utilities complete a thorough reassessment of
their needs for emergency power for system
operation.
11. All levels of government appropriately establish requirements for emergency power
sources for services essential to the safety and
welfare of the public, and ensure the availability of such facilities.
12. Utilities cooperate with appropriate public
officials and customers in planning and maintaining customer standby facilities to assure
service to critical loads in the event of
emergency.
CHAPTER 2
THE NORTHEAST FAILURE-REMEDIAL ACTlONS AND REQUIREMENTS
Circumstances of the Failure
The Northeast power failure began at approximately 5 : 16 p.m. on November 9,1965, and by 5 : 30
p.m. most of the northeastern United States and
much of the Province of Ontario, Canada was in
darkness. Power was interrupted for periods ranging from a few minutes in some locations to as much
as 13 hours in some parts of New York City. The
failure encompassed 80,000 square miles (figure 1) ,
and directly affected an estimated 30 million people
in the United States and Canada. It was by far the
largest power interruption ever experienced in the
United States. It dramatized the dependence of the
nation on electric power, and emphasized the
responsibility of the electric utility industry for providing virtually unfailing service.
Under its statutory responsibilities and in response to the urgent request of the President, the
Commission began its investigation immediately.
The Commission’s initial report, published December 6, 1965, pinpointed the initiating cause of the
POWER FAILURE
IN THE NORTHEAST
November 9-10, 1965
Generalized Areas of Outage
and .iome restorntrons over
lapped the boundaries
shown.
I5 mmutes to 3 hours
8. hours to 13 hours
FIGURB 1
interruption as the operation of a backup relay on
one of the five main transmission lines taking power
to Toronto from Ontario Hydro’s Sir Adam Beck
No. 2 Hydroelectric Plant on the Niagara River.
This relay, which was set too low for the load which
the line was carrying, disconnected the line. This
caused the flow of power to be shifted to the remaining four lines, each of which then tripped out
successively due to overloading. With the opening
of these lines, about 1500 megawatts of the power
being generated at Ontario’s Beck Plant and the
Niagara Plant of the Power Authority of the State of
New York, which had been serving the Canadian
loads in the Toronto area, reversed its flow and attempted to get to the Canadian loads through the
only remaining U.S.-Canadian tie at Massena. This
overloaded the Massena intertie and it opened, thus
completely isolating the Canadian system. As a result, a total flow of something over 1700 megawatts
to Canadian loads was blocked, and the power
surged into the United States. These flows exceeded
the capability of the transmission system in New
York and the interconnections to the south, and
triggered the breakup of the systems in Northeastern
United States.
The power failure .had three stages. The first
encompassed the initial shock to United States
systems from the sudden thrust of the 1700 megawatts of power from Canada. A widespread separation of systems through New York and New
England followed in a matter of seconds. If this
had been the end of the disturbance, the power
failure would have touched only one-third of the
customers who were eventually affected, and none
in southeastern New York and New England.
The second stage marked the attempted survival
of the electric utilities in eastern New York and
New England which had been separated from the
rest of the interconnected systems of the United
States. Isolated from other systems, these “islands”
(see\ figure 2) generally were left with insufficient
generation to meet their loads. Power generation
7
AREAS OF SEPARATION AT 5:17 PM
1.
2.
3.
4.
5.
Ontario Hydro System
St Lawrence Oswego
Western New York
Eastern New York - New England
Maine and Part of New Hampshir
.3ERvlcE AREA SEPARATIONS
NORTHEASTERN POWER FAILURE
NOVEMBER 9,1965
FIGURE 2
in virtually all of this area except Maine and eastern
New Hampshire (area 5, figure 2) ceased within a
matter of three to twelve minutes. During this
period, system operators attempted to interpret
the information provided by their control center
instruments, some of which were operating erratically, and to determine, with relatively little information, and in some cases with inadequate communications, the extent of the interruption and the
appropriate course of action each should take to
keep his particular system functioning.
The third stage of the failure-the restoration
of power-was prolonged in some areas of the region, particularly in New York City and Boston,
because power was not readily available to restart
the steam-electric generating units. Moreover, substantial delays were encountered in energizing the
high-voltage underground transmission networks.
The power failure revealed deficiencies in equip
ment, system planning, operation and maintenance,
and preparedness for emergencies. There were
problems with control equipment; there was a
more-or-less lack of auxiliary or emergency generating equipment; many transmission interties
proved to be inadequate; there were few welldeveloped plans for quickly balancing load and generation (load shedding and, in special cases, disconnection of generation) ; and provision for quick
restoration of service in the event of system failure
was often inadequate. The utilities in the affected
area have corrected or have made plans to correct
8
1
many of these deficiencies. Some of the measures
that have been taken to meet the obvious needs are
summarized later in this chapter. A more detailed
summary of actions by individual utilities is contained in appendices A and B. Many additional
studies are underway or planned to find solutions
to the more complex problems related to the re- 1
liability aspects of systems design and operation.
These are generally carried on as a part of normal iI
procedures, but the Northeast interruption has led
to a new recognition of their importance and
urgency.
The deficiencies revealed by the Northeast incident are the basis for most of the recommendations
contained in chapter 9 of this report. Many of these
recommendations, however, have general applicability to the development of power systems in other
parts of the United States and are not limited to the
Northeast.
!
Impact on the Public
The Northeast power failure affected the most
densely populated area of the nation. It caused inconveniences to about 30 million people and estimates of economic losses run as high as $100 million.
It left more than 800 hospitals without commercial
power, and in some cases, particularly in New York
City, no standby sources of power were availabie.
In some sections water and sewerage services were
interrupted. Fortunately, there were few fires during the interruption. Many persons were confined 16
for long periods in darkened elevators stuck bef
tween floors, and in subway trains stranded between
stations. Economic losses and impact on the public
welfare were greatly lessened because the failure
occurred on a mild moonlit evening. Public and
;
individual anxieties were moderated because tele’
phone service and many radio stations continued to
operate, using standby power supplies. Police functions were not seriously hampered because of continued telephone service and the availability to most
law enforcement agencies of self-contained power
units.
4
In order ta assess the full impact of the November
9th power failure on significant aspects of human
and institutional activities throughout the affected
area and the country at large, the Commission requested information from 30 Federal, state and
I
local bodies, on ( 1) their investigations and findings relating to a list of essential services, (2) actions taken, or in process, to prevent or alleviate the
impact on these services of possible future power
FICWRE 3 . 7
interruptior
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be supporte
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been taken i
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FIGURE 3.This 15,000 kw gas turbine generating unit was installed in December, 1966 for peaking and station startup
at Long Island Lighting Company’s Port Jefferson Station.
interruptions, and (3) their suggestions for additional services considered sufficiently important to
be supported by emergency electric power facilities.
The replies, which are summarized in appendix D
units in stairwells, elevator cars, transformers
and switchgear rooms, control centers, and
other specific areas;
indicate a generally high level of response to needs
ment of Housing and Urban Development, for
emergency transportation facility improvements, including emergency power supplies for
the movement of trains; the development of
emergency radio, station lighting and alarm
signal equipment; and the additions of other
essential facilities;
uncovered by the power failure. Actions that have
been taken include, for example :
A substantial upgrading of emergency lighting
and communication facilities at airports
throughout the country;
The development of emergency plans and procedures to insure that teletypewriters, PBX
and other telecommunications media could be
kept open and available to the public;
Initiation of a nationwide program to assure
that all civil defense warning telephones have
a constant power supply;
Initiation of a program to equip Federal government buildings with emergency lighting
The grant of Federal funds, by the Depart-
Upgrading of standby power capability for
communications and control during all critical
phases of space flight missions;
Promulgation by the City of New York of rules
to assure continuing adequate and safe functioning of hospital services and facilities during
power emergencies;
9
Action by the Port of New York Authority to
upgrade communication, lighting, and emergency evacuation procedures for facilities under
its jurisdiction.
date represent only the beginning of what needs to
be done to insure optimum reliability in the rapidly
expanding power systems being designed to meet
future needs.
These improvements are substantial, but deficiencies still remain in many vital areas. For example, a state-by-state survey by the Engine Generator Set Manufacturers Association of mandatory
provisions for standby power for essential services
indicates that 22 states have no legislative provisions requiring emergency power. Also a nationwide
study of auxiliary power available in the nation’s
hospitals as of 1965 showed that of 6,915 hospitals
surveyed, only 2,973 or 43 percent had adequate
emergency power.
The United States Congress has been concerned
about the Northeast power failure, its causes and
effects, and the remedial actions needed to minimize
the likelihood of future occurrences of this kind.
Particularly, the House of Representatives’Committee on Interstate and Foreign Commerce s and
the Senate Committee on Commerce,4 investigated
the circumstances surrounding the failure, its national implications, and subsequent actions undertaken by the electric power industry. The studies
and reports of these Committees reveal a widespread interest and concern throughout the nation
about the reliability of electric power systems. They
contain much information on actions taken or
planned by utilities, State Commissions and others
to improve system reliability and alleviate the effects
of power service interruptions. As random examples, the State of Montana has asked the utilities
within the State to so plan and schedule maintenance that only a minor portion of the state-wide
transmission system will be out of service at any time.
Evidence of similar concern is reflected in the State
of Michigan’s recommendations that its utilities improve their practices in periodic testing of system
control devices, and that isolated systems review
the advantages of interconnection in increasing reliability. Information assembled in the Committee
reports, however, suggests that accomplishments to
Status of Improvements in the Northeast
a See transcript of hearings before the Special Subcommittee to Investigate Power Failures, Committee on Interstate and Foreign Commerce, United States House of
Representatives, 89th Congress, and Addendum thereto.
Serial Nos. 89-40 and 89-54.
‘See Interim Report of the Committee on Commerce,
United States Senate on the Northeast Power Failure, Responses to Inquiries [Committee Print, March 15, 19661
89th Congress, 2d Session.
10
During the year following the Northeast power
interruption, the major affected utilities invested
$20 million in new equipment and improvements
to protect existing facilities and to lessen the likelihood of a recurrence of a cascading power systems
failure. An additional $30 million or more has been
committed for further improvements that are being made as rapidly as procurement and installation
schedules will permit. The following sections describe the typical major improvements completed
or underway.
Equipment Additions and Modifications
Every utility in the power failure area has reviewed the adequacy of its protective and control
equipment, and hundreds of modifications or additions have been made. Within a few days after the
power failure, the Hydro-Electric Power Commission of Ontario modified the protective backup relay
at the Sir Adam Beck Hydro Station which had
initiated the power failure, and additional relays
were installed to give the main transmission lines
improved protection and to permit their carrying
increased loads. As a further protective measure the
utilities in the United States that are interconnected with the Ontario system placed controls on
the two interconnecting transmission lines at
Niagara which, under any conceivable future mishap, would open these lines before power flows 1
reached levels likely to disrupt the operation of the
interconnected network in New York and adjoining
areas. Thus, the probability of another power failure
from the same precipitating cause is very remote.
Many of the dual-scale frequency meters which
confused system operators when extremely subnormal frequencies occurred have been replaced with
I
two separate instrument-ne with a magnified
scale to show small deviations during normal operations and the second to indicate the wide frequency deviations that occur during severe system
disturbances.
A serious deficiency uncovered by the Northeast
failure was the frequent lack of emergency power
to provide lights and communication at control centers; to protect generation facilities during the run-
down pe:
mum de1
of gener:
some are:
Utilitic
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down periods; and to restart generators with minimum delay. This resulted in damage to a number
of generators 5 and prolonged the interruption in
some areas, notably New York City.
Utilities in the Northeast and in many other parts
of the country have installed or have on order the
auxiliary power units needed to maintain station
service and to restart steam-electric generating stations following a shutdown when other sources of
start-up power are not available. Plants in the
,Northeast and in the Pennsylvania-New JerseyMaryland area are adding G 62 units with an aggregate generating capacity of 1,025,OOO kilowatts,
primarily to assure that adequate starting power will
be available. Many of the units can also be used to
help meet peak loads during normal operation. Because of the time required for delivery of this equipment, for which an especially large demand has
arisen since the power failure, only a small part of
the equipment ordered is now installed. By the end
of 1967, all of the units should be ready for service.
Where hydroelectric power is readily available,
systems are relying upon, this source for quick startup power, and some are arranging circuits for simplified switching in time of need.7 Systems which
had access to hydroelectric power were among the
first to restore service on November 9.
Appendix B, table B-l, summarizes the major
improvements that have been made at generating
stations in the Northeast that have capacities of
100,000 kilowatts or more. These stations represent
nearly 90 percent of the total capability of the systems involved.
’Altogether, five units in the island area having a rated
capacity of 1,945,OOO kw were damaged and were out of
service from three weeks to two months.
‘Installed or ordered between November 9, 1965 and
March 31, 1967.
‘Nine utilities in the Northeast have made changes in
facilities or operating instructions to assure that hydro
power can be quickly routed to thermal plants for station
service. For example, Central Vermont Public Service
Corporation has rearranged the station service wiring at
its Rutland Gas Turbine Station so that station service
can be obtained from a nearby hydro station. The
CONVEX Pool has established emergency switching procedures to expedite the routing of emergency auxiliary
power to the West Springfield Steam Station from Cobble
Mountain Hydro Station and to Mt. Tom Steam Station
from the Cabot Hydra Station. General Public Utilities has
established an operating procedure to retain a minimum
elevation in the upper reservoir of Yards Creek Pumped
Storage Plant so that this station can serve as a source of
cranking power for thermal plants.
,“”
,-
Spinning Reserve Practices 8
The function of spinning reserve in the operation
of a power system is to provide additional generation quickly whenever it is needed. Such reserves
enable an interconnected system which has encountered difficulty, such as the sudden loss of a generating unit, and which is temporarily being supported by small increments of power from many
units of the network, to rebuild its own supply
rapidly and restore tieline flows to normal. It is
not always practical to carry enough quickly responding spinning reserve to permit complete
restoration of needed generation in an area
that becomes an “island” (separated from the interconnected system) after a severe disturbance. Such
was the case when the Southeast New York-New
England area became an electrical island on November 9. A contributing problem in the island
area was the concentration of spinning reserves in
the Southeast New York area, resulting in a substantial increase in system losses when the island
was formed.
The combined response of the spinning reserve
in this area on November 9 immediately following
the separation is depicted in figure 17, chapter 5,
and is discussed in detail in the excellent studies
of the Task Force which appear in Volume III.
The responses of individual units varied widely.
Some with considerable steam reserve in the boilers
responded quickly, but the energy stored in the
boilers became exhausted in less than 30 seconds
and was not replenished at normal rates because
the declining system frequency and voltage seriously
impaired the capacity of the units’ auxiliaries which
service the boilers. Other units served by boilers
which operate with more limited heat storage
capacities were slower to respond because increased
steam output is dependent upon increasing the
fuel supply rate and a related series of actions
which necessarily produce a lag in the fuel inputsteam output sequence.
As this discussion has indicated, to expect spinning reserves to meet such extreme situations is to
anticipate performance beyond their usually assigned function. The experience demonstrates that
performance cannot be measured merely by numerical addition of excess machine capacities above current outputs; the speed and amount of sustained
response over an interval of time must also be
a See also the discussion on System Reserve in chapter 5.
11
considered. The overall dependable rate of response
of a group of steam turbine generators is improved
by distributing the spinning reserve over a large
number of the units. In this respect, the practice
which prevailed on November 9 in the Northeast
nee-ded some improvement.
Provisions for load Shedding o
The best protection against a power interruption
is sound planning and a well designed and operated
bulk power supply system. It remains conceivable,
however, that at some time an unexpected event
can isolate a utility or group of utilities from the
network. If the island area thus created is deficient
in generation, loads must quickly be reduced to
avoid total collapse of the power supply system.
Manual load shedding is likely to be accomplished too slowly during a severe emergency, so
automatic controls are needed to assure that load
shedding will effectively serve its intended purpose.
On November 9, the southeast New York and New
England utilities became an electrical island five
seconds after the disturbance began, but the island
system did not collapse until 12 minutes after its
separation. During that period, system voltage and
frequency fell far below normal and the capability
of the generators which remained in operation
declined rapidly.
A separation of the network caused by a severe
disturbance usually creates an “electrical island”
encompassing a number of utilities. Unless load
shedding is effected automatically, the load reduction of each utility would be subject to the promptness of its operators in decision-making and actions,
with a resulting pattern of overall load reduction
that could vary widely from the planned objective.
Even rigorous drilling and training of operators in
manual operation would not be completely effective
because of the need for quick determination and
action involving speeds beyond human capabilities.
Moreover, uncoordinated manual load shedding by
one utility might not be properly timed with respect
to similar actions by adjoining utilities using either
manual or automatic controls. To be effective, automatic load shedding equipment must be designed
to provide adequate relief under all foreseeable
circumstances.
“The purpose and problems of load shedding are discussed in greater detail in chapter 5.
At the time of the interruption, no utility in the
CANUSE lo area employed automatic load shedding. This is in marked contrast to some other parts
of the United States where it is employed extensively. Automatic load shedding procedures, however, have recently been adopted by all major utilities in the Northeast, as a result of the efforts of
the Northeast Power Coordinating Council.*1 The
agreed upon procedures should be implemented as
quickly as the necessary equipment can be designed
and installed:
Service to New York City
The interruption of November 9 placed New
York City, the center of the largest metropolitan
area in the world, in total darkness. At the time of
the interruption, Consolidated Edison Company was
serving a load of 4,770,OOO kilowatts. The installed
capacity of the Company’s generating equipment
was about 7,580,OOO kilowatts. The Consolidated
I
Edison system collapsed not because of a direct
generation deficiency within its own area, but
because of the effects of deficiencies in the interconnected system, the rapidly changing conditions
during the disturbance, inadequate information to
the system operator, and lack of automatic controls
to restore balance.
Since the failure, the Company has improved its
systems of instrumentation and control. It has installed separate wide band and narrow band frequency meters at its control center in order to avoid
the hazard of misreading the scale. It has provided
alternative power sources which can furnish
continuously available and reliable power during
system disturbances for all of its communication systems, including power supplied for the transmission of system performance data by telemetering
and other communication equipment.
The density of power service in the City of New
York, and the extensive use of underground cable
feeders added to the task of restoring power. The
magnitude of loads required separation of the cable
system into sections to prevent potentially harmful
overloading of some circuits. Furthermore, reenergizing large sections of underground cable must
XI Canada-United States Eastern Interconnection, an
informal coordinating organization that includes representatives from utilities in Michigan, the Hydra-Electric
Power Commission of Ontario, and utilities in the
Northeast.
“The Council is described in the last section of this
chapter.
FIG
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FIGURE
4.-Emergency standby power for safe rundown is provided by this 600 kw diesel engine generator set at Consolidated Edison Gompany’s Hudson Avenue generating station.
be done with caution to prevent excessive voltage
and damage to equipment. Compensating devices
are being installed on the underground cable
system to minimize the likelihood of equipment
damage.”
Emergency power standby units have been ordered by the company and are being installed at
various generating stations. Small emergency units
are being installed to maintain dil pressure on bearings of generating units during rundown and to
keep the hot units in slow rotation should power
again be totally interrupted for any reason. Larger
units up to 20,000 kilowatts capacity will supply
power to steam station auxiliaries to enable restart
of major generating plants in the event that other
sources of startup power are lost. These large standI2 The Company has installed 680 megavars of compensation in the form of shunt reactors on its underground
cable transmission system. Another 860 megavars have
been authorized, most of which will be added by 1969.
by units also can contribute to the system reserve
capacity or be operated to help meet short time
peaks.
The Company has placed in effect a system of
load shedding through automatic voltage reduction which will be applied in two steps by the action
of underfrequency relays. These steps are expected
to reduce loads about 5 and 3 percent, respectively,
in areas serving about 75 percent of the system load.
In addition, the Company has agreed to the automatic and manual load shedding procedures
adopted by the Northeast Power Coordinating
Council.13 System controls are arranged at present
so that practically all loads can be interrupted by
la The schedule provides for automatically reducing
loads 10 percent when system frequency is in the 59.5-59.0
c.p.s. range and an additional 15 percent when system
frequency deteriorates to the 59.0-58.5 c.p.s. range. If
the emergency situation continues, an additional 25 percent of load will be shed manually.
13
the pushing of supervisory control buttons in the
Company’s system control center.
The readiness of the Company to cope with an
under-frequency situation will be substantially improved when the automatic provisions cited above
are fully installed. The operating program ‘now in
effect relies entirely on the judgment of the system
operator to shed loads manually if automatic voltage
reduction is insufficient. This places an excessive
responsibility on individuals to take timely and correct action under emergency stress, and unnecessarily
subjects the city’s power supply to significant risk.
Although skilled operators have been able to bring
systems through critical subnormal frequency situations without interrupting loads, the margin between success and failure can be very narrow. The
automatic load shedding procedures that have been
agreed to by the Northeast Power Coordinating
CounciI should be implemented as rapidly as
possible.
Power for New York Subway
Since November 1965, officials of Consolidated
Edison Company and the New York City Transit
Authority have been conducting studies to determine the best means of strengthening service reliability to the subway system. The failure left parts
of the system without power for nearly ten hours.
The BMT (the old Brooklyn-Manhattan Transit)
and IRT (Interboro Rapid Transit) use 25-cycle
power and the IND (Independent) system is supplied from the 60-cycle network.
Consolidated Edison has ordered ten gas turbine
generators ranging in size from 11,000 to 20,000
kilowatts for emergency and peak-power requirements. While these gas turbine units are intended
primarily for starting power in the event of another widespread failure, they will also be, able to
furnish sufficient power to permit the BMT and
IRT trains to reach the next station. The situation
on the IND system% different. This system is supplied from the 60-cycle network which also supplies
the general utility loads, and it is not possible to
afford it selective treatment in either protection
from interruption or restoration of service if the
system loses all power. However, Consolidated
Edison is looking’ into the possibility of providing
a minimum number of single-duty 60-cycle feeders
to selected rectifier stations (perhaps every fourth
station along the subway line) to make it possible
to move stalled trains at least into the next station.
14
Service to Boston
The power failure in Boston on November 9, was
generally similar to that in the. New York area. The
Boston Edison Company load just prior to the interruption was 1,375,OOO kilowatts, including
174,000 kilowatts being exported. Sufficient capacity was available to meet these loads plus
spinning reserve requirements. Nevertheiess, the
system had completely collapsed by 5 : 21 p.m.about five minutes after the initial disturbance.
Charts from recording instruments indicate that
system conditions were changing so rapidly during
the five minutes, that it was impossible for the system operators reasonably to interpret all the events
that occurred. The disturbance in the Boston area
was aggravated by the tripping of 16 generators on
the New England-Eastern New York systems by
loss-of-field relays.14
Some of these units did not have high speed automatic voltage regulators and others were being
operated with the regulators out of service. The
units might have remained in operation if fast response voltage regulating equipment had been
operative.15
Restoration of service in Boston was delayed by
the lack of emergency power sources for unit
start-up. After more than an hour, start-up power
for one station was obtained through a 13.8 kilovolt
connection to the U.S. Naval Shipyard in the
Charlestown section of Boston. Other units were
started in sequence until the system was virtually
restored to normal about 71/z hours after the beginning of the trouble.
Boston Edison’s basic problems were those common to most of the “island” area-too much load
for the available generation, lack of an effective
program of rapid load reduction in an emergency,
and no readily available sources of emergency
power for restoration of generating units after the
system had collapsed.
Recognizing these problems, Boston Edison has
installed a jet-engine generator for emergency starting power and four small diesel engine generators
for safe rundown. Underfrequency relays have
I’Loss-of-field relays are used to detect trouble in the
excitation systems of generators. If serious trouble occurs,
the relay acts to disconnect the generator to minimize
damage to the machine and prevent development of an
unstable condition on the power system.
15Discussion of the importance of fast response voltage
regulation is included in the report of the Eastern New
York-New England System Studies Group in Volume III. ,@
been instalk
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been installed to isolate a steam unit with sufficient
auxiliary load to permit its continued operation during any severe system disturbance. This unit can
then provide power for restarting other units. Manual load reduction procedures are in use and automatic load shedding incorporating the Northeast
Power Coordinating Council’s recommendations is
being planned. Until installed, some danger remains
that system power could be totally lost if Boston
should again become part of a distressed power
island.
, The Boston subway and elevated transportation
systems were not interrupted since they were supplied from independent power plants of the Massachusetts Bay Transportation Authority which continued to operate during the disturbance.
Studies of the Northeast Network
Immediately following the failure of November
9, the Commission initiated a series of intensive
studies of the Northeast transmission network l6 to
determine its ability to respond to severe faults and
losses in either load or generation. These studies
were conducted under the general guidance of the
Commission and its Advisory Panel on the Northeast Power Interruption by task groups ‘organized
under the Commission’s direction.
The network as it existed in January 1966 was
examined under 13 assumed possible, although improbable, occurrences similar in magnitude and
severity to that experienced on November 9. These
13 selected cases were representative of a large number of potential improbable situations that could
conceivably occur in various places on the system.
They have no special significance from the standpoint of specific location or type of occurrence. The
selection was guided by types of failures in equipment which have occurred on power systems in the
past.
Most of the cases tested are characterized as
“double contingencies,” since they combine the occurrence of a severe incident with the prior or simultaneous occurrence of another serious incident.
Examples are loss of a large generating unit follow“The power failure involved primarily the New England States and New York. However, from the standpoint
of close coordination of overall system planning and operation, the Pennsylvania-New Jersey-Maryland (PJM) interconnection is a vital link in the strength and reliability
of the Northeast area systems. Consequently, the PJM
system must be considered in planning future expansion,
interconnection, and control for the Northeast systems.
ing loss of a major transmission line, the simultaneous interruption of two transmission lines on the
same corridor or the failure of a breaker to
clear a severe fault on a main circuit promptly. The
test results indicated both stable and unstable
conditions.lT
Further stability studies were made of the Northeast network as strengthened by three new transmission interconnections scheduled to be in operation
by 1968.l’ One of these, a 230 kilovolt extension of a
western New York-Pennsylvania tie into northern
Ohio, was placed in operation a month after the
power failure. A second interconnection, in effect
strengthening an existing transmission link between
Public Service Elect.& & Gas System in New Jersey
and Consolidated Edison in New York City, will be
fully completed by the end of 1967. It consists of a
new 345-kilovolt transmission line between the Consolidated Edison Company’s Arthur Kill Generating
Station on Staten Island and its Farragut Switching
Station in Brooklyn, now in service, and conversion
of the present 138 kilovolt tie to Public Service to
230 kilovolts. These changes will increase capacity
for the flow of power into New York City under
emergency conditions from 300 megawatts, the
present limit, to 500 megawatts. The third addition
is a 500 kilqvolt intertie from Pennsylvania and
New Jersey to southeast New York. This line will
have a carrying capacity of about 1,000 megawatts
and is intended primarily to strengthen the interconnection. The purchase or sale of firm capacity
over this intertie is not contemplated during the
early years of its operation. Consequently, practically the entire capacity of the intertie should be
available for emergency or reserve interchange.
The studies show that these added interties will
substantially improve network stability. However,
the 500-kilovolt intertie from Pennsylvania and
New Jersey to southeast New York has been delayed
by right-of-way problems in New Jersey and now is
not scheduled for operation until the summer of
1969. This seriously prolongs the present deficiency
in interconnection capacity between the Northeast
and the P JM load areas.
Various groups of utilities in the Northeast have
sponsored several independent studies by private
consulting firms, among these a study of the Northeast interconnection Is by Stone and Webster Engi“The report of the task group which performed these
studies is included in Volume III of this report.
“A summary of the report of the Stone and Webster
Corporation is included in Volume III of this report.
15
neering Corporation. Thk consultant examined the
effects of severe disturbances, involving loss of lines
or generating units, on system stability. For many of
the cases, it was concluded that system separation
was a possibility. Even so, there is some question
about whether the criteria for assumed disturbances
were sufficiently severe. The study was made primarily to develop general guidelines for increasing
reliability rather than to produce plans and designs
for system changes. The consultant’s report sets
forth recommendations relating to criteria for stability examinations, spinning reserve, automatic
voltage regulation, restoration of tielines, establishment of system security centers for continually monitoring system conditions and performing security
analyses, and suggested requirements for automatic
load shedding.
Prqjectionr of Development by Northeast
Utilities
I
Figure 5 depicts the principal elements of the
transmission network in the Northeast and interconnections with adjoining areas, and delineates
lines added since the power failure of November 9
and those scheduled for addition up to 1973. The
projections are in response to the Commission’s request for a six-year forecast of load, generation, and
transmission requirements. In the period from November 1965 to 1973, 1400 miles of 345-kilovolt circuits and nearly 300 miles of 500-kilovolt circuits
have been or are scheduled to be placed in service in
the Northeast. The peak load projected for the
Northeast I9 systems for the winter of 1973 is 31,200
megawatts, an increase of 35 percent over the area
peak load projected for the winter of 1967. Planned
generating capability in the area is 40,300 megawatts, an increase of 44 percent above the capability
in 1967. The gross margins of capabilities above projected peak loads for the period of 1969 to 1973 is a
minimum of 29 percent and averages about 30 percent, substantially more than the 21 percent available in 1967.
The portion of the gross margin of future generation that will exceed the requirement for reserves
is dependent upon such things as required downtime for maintenance, flow conditions at hydro installations, lead time for construction of new units,
and inaccuracies in load forecasts. The fact that
indicated gross margins are high does not necessarily
“Not including the Hydro-Electric Commission of
Ontario.
16
mean that they are excessive. Nevertheless, in the
Northeast where planned system improvements will
enhance the opportunities for improving coordination of construction and maintenance programs, the
figures in the preceding paragraph suggest that a
careful review of gross margin requirements might
lead to some substantial savings in construction investments without sacrificing reliability.
EXlSTlh
Need for Further Study
Continuing study of the Northeast network and
its ties to neighboring systems is essential to assure
continuous stable operation in the face of rapidly
increasing loads. The Northeast Power Coordinating Council has initiated a region-wide stability
study of the configuration of generation and transmission contemplated for 1973. These studies have
not progressed sufficiently to judge the adequacy
of the network for the projected 1973 loads, but
additional strengthening may be needed to reduce
the possibility of network separation. The Commission’s Advisory Panel for the Northeast Bower Interruption, in reviewing the task group studies and
projected programs of the Northeast utilities has
stated :
. . . The Panel believes that the proposed increased
distribution of generation and its location closer to the
load centers, particularly in thermal and pumped storage
plants, should strengthen the network in the future by reducing some of the need to transport power over substantial distances in the area. This, thereby will relieve
transmission capacity for backup purposes during outage
contingencies. The Panel suggests that further consideration be given to additional interconnections, particularly
to the South and West from upper New York State. This
judgment was arrived at by noting the future proposed
345-kv and 500-kv developments in this and adjacent
areas. While the Panel is in no position to determine
whether such lines are essential, it, nevertheless, believes
that any additional reinforcing ties of this type would contribute greatly to the overall reliability of the area, particularly because of the area’s somewhat radial relationship
to the systems to the South and West.*’
Provisions for strengthening interconnections, not
only in the Northeast but throughout the nation,
are discussed in chapter 6. The discussion presents
a general pattern which, on the basis of rough appraisals, will be needed by 1975 to prevent the recurrence. of cascading power failures. Suggestions
2o Comments by the Advisory Panel on the Northeast
Power Interruption on the Task Group Studies are included in Volume III of this report.
beyond
ordinal
general
f The N
i
’
,
:
One
elusion
improt
formin
fective
planni
nating
MAJOR TRANSMISSION LINES AND GENERATING STATIONS
EXISTING AND PROPOSED IN THE NEW YORK AND NEW ENGLAND POWER SYSTEMS
AS OF JANUARY 1967
FICWRE 5
beyond those outlined by the Northeast Power Coordinating Council for 1973 are included in this
general pattern.
The Northeast Power Coordinating Council
One of the immediate and most significant conclusions from the power failure was the need for
improved coordination among the many utilities
forming the Northeast interconnection. To be effective, such coordination must encompass both the
planning and operating functions, and the coordinating mechanism must provide a satisfactory means
for reaching timely agreement. Improvement in coordinating organizations throughout the nation to
achieve better reliability of bulk power supplies is
one of the principal recommendations of this report.
A step forward toward closer coordination among
utilities in the Northeast was achieved by the formation of the Northeast Power Coordinating Council
in January 1966. Its members include 21 21 major
utilities in the Northeast and the Hydra-Electric
Power Commission of Ontario (figure 6).
The work of the Council is carried out under the
direction of an Executive Committee of nine members and a Chairman who is also the Chairman of
the Council. There are two principal standing committees-the System Design Coordination Committee and the Operating Procedure Coordinating
Committee. The work of these committees is supn Including Connecticut Light & Power Company,
Hartford Electric Light Company, and Western Massachusetts Electric Company recently consolidated into
Northeast Utilities.
17
I
MEMBER SYSTEMS OF
NORTHEAST POWER COORDINATING COUNCIL
L
1
i
DO
ha
sy !
ha
th
ro
of
m
PENNSYLVANIA
1 BOSTON EDISON COMPANY
2. CENTRAL HUDSON GAS 6 ELECTRlC
CORP.
3. CENTRM MAINE POWER COMPANY
4. CENTRAL VERMONT P”BL,C SERVlCE
CDRP
5. CONNECTICUT LIGHT AND POWER
COMPANY, THE
6: CONSOLIDATED EDISON COMPANY OF’
NEW YORK, INC.
I EASTERN UTILITIES ASSOCIATES
8. G~A;$UNTAiN POWER CORPO9. HARTFORD ELECTRIC LlGHT
COMPANY, TNE
IO. HOCYOKEWATER POWEROOMPANY
ANDHOLYDKEPOWERhELECTRlC
COMPANY
1,. HYDRD-ELECTRIC POWER CO~,SSIC,,
OF ONTARIO, THE
12. LONG ISLAND LIGHTING COMPANY
13 NEW ENGLAND ELECTRlC SYSTEM
14. NEW ENGLAND GAS AND ELECTRlC
ASSOCIATION
IS. NEW YORK, STATE ELECTRlC & GAS
CORP.
lb. NIAGARA MOHAWK POWER CORPDRATION
Il. ORANGE AND ROCKLAND UT, LITIES,
INC.
18. POWER AUTHORITY OF THE STATE
OF NEW YORK
19. PUBLIC SERVICE COMPANY OF
NEW HAMPSHIRE
20. ROCHESTER GAS AND ELECTRlC
CORP.
21. UNITED ILLUMINATING COMPANY,
THE
22. WESTERN MASSACHUSETTS ELECTRlC
COMPANY
FIGURE 6
plemented by task forces on system studies, system
protection, load and capacity, load shedding and
spinning reserve, and computers.
Many of the Council’s activities since organization have been related to seeking solutions to problems revealed by the Northeast power failure, many
of these in direct response to the request of the
Federal Power Commission. Major efforts of the
Council’s committees have included stability studies
of the Northeast network (partly in valuable assistance to the Task Group Studies, summarized in
18
Volume III), projections of load, generation, and
transmission requirements by 1973, and coordinated
study of load shedding.
Recently, members of the Northeast Power Coordinating Council adopted an automatic load shedding program. Th e program provides that each
system will be equipped with underfrequency relays
which will drop 10 percent of system load should
frequency decline to 59 cycles and 15 percent more
at 58.5 cycles. Each svstem will urovide for dropping, manually, an additional 25 percent of its load
whenever emergency conditions warrant. Prior to
this agreement, the Niagara Mohawk Power Corporation was the only member of the NPCC which
had undertaken installation of a comprehensive
system of automatic load shedding, although a few
had installed some automatic equipment.
Stability studies of the transmission network projected for 1973, tested under the severe criteria reviewed earlier in this chapter, are in process and are
scheduled for completion later this year. It appears
that the Northeast utilities and also those in surrounding areas will need to expand their analyses
of the integrated regional and interregional transmission requirements. The Commission has urged
bE STATE
NYDF
.KTRlC
UMPANY,
IS ELECTRIC
ation, and
1 coordinated i
t Power Cotic load shed:s that each
luency relays
load should
lercent more
de for dropnt of its load
the Council to intensify its efforts and to expand its
analysis of future requirements.
The Council also has reached agreement on the
establishment of two central control centers for
coordinating the operation in 1970, one for systems
in the State of New York and the other for systems
in the New England area.
Council officials report increasing awareness of
the value of coordination among its members. We
believe these values would be further enhanced in
the region if all ownership classes of bulk power
supply entities in the Northeast region were represented in the Council membership, and actively participated in Council undertakings.
CHAPTER 3
POWER INTERRUPTIONS AND INTERRUPTIONS AVOIDED
Power Interruptions
Since the November 1965 Northeast power failure, the Commission has investigated and reported
upon most of the significant interruptions in the
nation’s bulk power supply. Twenty interruptions
are briefly described in this chapter which have
occurred at widely scattered points in southeast and
southwest Texas, Alaska, the Pacific Northwest and
Rocky Mountain areas, southern California, Nebraska, Missouri, Ohio, Virginia, and the PennSylvania-New Jersey-Delaware-Maryland area. All
but three of these twenty interruptions were cascading failures. The largest of these occurred on
June 5, 1967, and interrupted power service to
eastern Pennsylvania, New Jersey, and the Delaware-Maryland peninsula. The failure affected 13
million people and lasted for periods up to ten hours.
TABLE
This failure is described separately later in this
chapter. The principal circumstances of each failure are summarized in table 1.
These occurrences illustrate the variety of circumstances which can cause power interruptions.
They also reveal that a single precipitating cause may
affect many generating or transmission facilities,
that a failure of one element can contribute to the
failure of others, and that protective devices must
operate reliably to be effective.
For example, in Beaumont, Texas, a defective
element in a supervisory control system, which permits operators to perform switching operations from
a central station, opened a high voltage transmission
line and a few minutes later disconnected a principal generating station.
l.-Major power failures which have occurred subsequent to the Northeast failure.
El Paso, Texas, December 2,1965
Los Angeles Power Failure, January 24, 1966
A loss in load of 267,000 kilowatts for periods up to two
hours and ten minutes affecting 470,000 persons in the
United States and 100,000 in Juarez, Mexico, was caused
by the accumulation of condensates in the gas supply line
to the El Paso Electric Company’s principal generating
station. The movement of condensates into the generating
plant operated protective controls which shut ofs the
burners. This major loss in generation, amounting to 51
percent of the system’s output at the time, caused the
115-kilovolt tieline to the north to become overloaded and
trip out. The emergency capability of this line is about 40
megawatts.
Power was interrupted for periods of 11 to 31 minutes,
affecting an estimated 200,000 customers in the northwest
section of the city. The interruption was triggered by the
programed opening of two 138-kilovolt lines to permit construction on an adjacent new 230-kilovolt circuit. Two
138-kilovolt lines in another section of the network became
overloaded following this switching operation and relayed
open, followed in turn by the opening of some intermediate
230-kilovolt circuits. Underfrequency relays dropped approximately 20 percent of the city’s load, permitting the
system to stabilize.
Vicinity of Beaumont, Texas, December 6, 1965
An interruption in bulk power supply occurred on the
interconnected systems in the Anchorage area, extending
from Seward to Palmer, affecting a population of 125,000
for periods up to nearly two hours. The interrupted load
amounted to 54,400 kilowatts. The failure was initiated by
a prankster throwing a length of wire across a 34-kilovolt
line. A protective relay on this line malfunctioned and the
fault was cleared by breakers on the main 115-kilovolt
line which tripped out. With the loss of power supply from
Eklutna over this line, the generation in the Anchorage
area was insufficient to meet requirements and the entire
Anchorage area load was lost.
Malfunction of supervisory control equipment caused
the opening of a 138-kilovolt transmission line, and subsequently tripped all units of a principal generating station
on the western section of Gulf States Utilities Company’s
system. As system frequency declined, attempts were made
to isolate a portion of the Gulf States’system and transfer
the load temporarily to Houston Lighting and Power. The
remote control switching did not operate as planned, and
the section lost 79 megawatts for 26 minutes. Protective
devices on industrial loads of the western section dropped
approximately 140 megawatts of load for periods up to
three hours.
Anchorage, Alaska and Vicinity, May 13, 1966
TABLE l.-Major
power failures which have occurred subsequent to the Northeast failure-Continued
Western States Power Interruption, April 26, 1966
An inaccurate telemetering signal caused an overgeneration of power in the Pacific Northwest which overloaded and tripped off several long distance interconnecting ties. As a consequence, the western interconnection
was separated into five major and two minor areas. To prevent collapse of power in some of the distressed separated
systems, some 505 megawatts of load, mostly industrial,
was dropped for periods up to 56 minutes. The last tie
restoring the interconnection was closed five hours after
the interruption.
Western States Interruption, June 7, 1966
A high speed ground switch associated with a 230/345kilovolt transformer bank malfunctioned and caused a
widespread tripping of tie lines in the western interconnection, separating it into eight isolated areas. A total of
848 megawatts of load was interrupted for periods up to
40 minutes. The interconnection was restored in less than
two hours, except for the 230 and 345kilovolt lines initially interrupted. These were closed on the next day.
Nebraska Interruption, ]uZy II,1966
Two power failures occurred on the same day in the
Nebraska-Dakota areas, the first from incorrect wiring of
a relay, and the second from failure of a power transformer.
The two interruptions caused widespread separation of
systems in this area, and in each instance 800 megawatts of
load was interrupted. Power was restored in about three
and one-half hours following the first interruption, and in
two and one-half hours after the second. About 600,000
persons were affected by the loss in service.
Western States Interruption, July 12,1966
A severe lightning storm caused the opening of breakers
at a principal station near Spokane, Washington, which
tripped seven 230-kilovolt transmission lines in the area.
The resulting interruption separated the interconnection
into eight major isolated areas. The load interruption exceeded 975 megawatts for periods up to 32 minutes. The
interconnection was restored approximately 20 minutes
after separation,
Forced Curtailment of Electricity in the St. Louis Area,
July 11 and 12,1966
The forced curtailment of power use in the St. Louis
area began at 1: 47 p.m. on July 11 and amounted to a
reduction of about 300,000 kilowatts from the 3,500,000kilowatt load which would have developed without the
curtailment.
The problem was precipitated by a period of abnormally
hot weather accompanied by high peak loads coupled with
the unavailability of the new 478,000-kilowatt generating
unit at the Portage des Sioux station, originally scheduled
for initial service on May 1, 1966.
All interruptible loads, totalling about 55,000 kilowatts,
were cut off at 8: 15 a.m. on July 11. Telephone contacts
with industrial customers netted some voluntary curtailments and spot radio announcements gained some additional voluntary reductions in residential, commercial, and
industrial loads. Beginning at 1: 47 p.m., some low-priority
loads were cut off on a rotational basis, and this continued
I
j/!
Ilj
22
the VEP
bus to 01
In additi
to the n
into the
load was
mission !
until 3 : 50 the next morning. Such curtailments were resumed from 11: 30 a.m. to 7 : 30 p.m. on July 12. Although
power was available from utilities to the north and east,
interconnecting transmission lines were able to move in
only about 176,000 kilowatts of emergency assistance.
Western States Interruption, July 18,1966
A telemetering error affecting the interchange power
flows resulted in overgeneration on the power system. The
overgeneration tripped
a number of the weaker ties and
_separated the interconnection into five isolated areas.
Loads totalling 3 12 megawatts were interrupted for periods
up to 30 minutes. The last tie line was reclosed in one
hour and 15 minutes.
Arkansa.
A set
line was
circuit s
service 1
remainir
system h
56,700
hour an
some 5,’
295,000
Southern California Edison Company, July 19, 1966
The 1,465,000-kilowatt output of the Company’s Alamitos steam electric generating station was suddenly interrupted by the failure of two 230-kilovolt air-blast circuit
breakers in the plant’s switchyard. This loss amounted to
about 25 percent of total system generation at the time
and resulted in overloading and opening all ties with other
utilities. The Company’s underfrequency relays acted instantly to drop major blocks of load. Including lesser loads
which were shed manually, the reduction totalled about
1,300,OOO kilowatts:Ties to other systems were restored in
a few minutes and service to all customers was restored
within 27 minutes following the interruption. The generation deficiency following interruption on the Southern
California Edison Company’s “island” operation was
larger in magnitude than the deficiency experienced in
the Northeast power failure in the eastern New York-New
England islaud area, and much larger in proportion to the
total load in the island areas. In California, a prolonged
total system collapse was averted because the emergency
situation was instantly countered by automatic load shedding.
Western States Interruption, July 21,1966
A’ defective relay opened a 230-kilovolt transmission
line between Walla Walla and Wanapun, Washington.
The subsequent adjustment of flows resulted in other lines
being tripped on overload, and the western interconnection
was separated into seven areas. Approximately 590 megawatts of load was shed for periods up to 43 minutes. The
final closure of all ties was not completed until more than
ten hours following interruption.
Western States Interruption, August 1,1966
Bonneville Power Administration’s McNary-Roundup
line was inadvertently tripped when its relays were being
reset. Overloads on other lines caused the western interconnection to separate into four isolated areas. Approximately 445 megawatts of load was lost for periods up to
45 minutes. The interconnection was restored to normal in
five minutes.
Virginia Electric B Power Company System, November
3, 1966
i:
I
Austin,
1966
Simd
breaker!
o f eleci
50,000 1
was red
determi
system i
Gulf St
A PO
t
May 11
Cornpar
Doucetl
About
tion w:
which i
of a 5
general
megaw
later, E
138-kilt
and set
eight n
Gulf SI
at the
comple
second:
Attem
shift st
unsucf
resuitt
In J
The interruption was caused by the explosion of a 115- m
kilovolt circuit breaker at the government-owned Kerr E’ son Cc
statior
Dam project. The fault caused five 115-kilovolt circuits in 1
TABLE
l.-Major power failures which have occurred subsequent to the Northeast failure-Continued
the VEPCO system which connected to the government
bus to open under back-up protection at remote locations.
In addition, a 115-kilovolt breaker at a subs&on 80 milts
to the north opened due to overload and severed supply
into the area from the north. About 155,000 kilowatts of
load was interrupted, affecting 150,000 customers. Transmission service was restored to the area in 45 minutes.
Arkansas-Missouri Power Company, December 2, 1966
A section of the Company’s 115-kilovolt transmission
line was knocked out of service by a felled tree. Another
circuit supplying Arkansas-Missouri had been taken out of
service previously for re-insulating work. The Company’s
remaining ties and plants were overloaded interrupting
system load amounting to 91 megawatts and approximately
56,700 electric customers. Service was restored in one
hour and seven minutes throughout the area which covered
some 5,800 square miles with a population estimated at
295,000 persons.
Austin, Texas, Munici#al Electric System, December 14,
1966
Simultaneous trip-out of three 69-kilovolt circuit
breakers at the System’s Holly Street Plant caused a loss
of electric power of 120 megawatts to approximately
50,000 customers, in the city of Austin. Complete service
was restored in 40 minutes. The exact cause has not been
determined but a malfunction in the supervisory control
system is suspected.
Gulf States Utilities Company, May II, 1967
Under-frequency relays l&&l not yet been installed on the
company’s system.
Cleveland Electric Illuminating Com.pany, May 17, 1967
At 11: 59 p.m., EDT, an interruption affected approximately 66,000 customers and 80,000 kilowatts of load
in the Greater Cleveland west side area of Cleveland,
Ohio. No equipment trouble was found and all service
was restored within 28 minutes. The interruption occurred during a labor strike, and the four 132 kilovolt
transformer breakers found open at the Clinton Substation were believed to have been tripped manually in the
switchyard. The substation had been the scene of heavy
picketing, and barbed wire barriers at the top of the main
switchyard gate and fence were found cut.
Cincinnati Gas and Electric Company, May 26, 1967
At 9:29 p.m., EDT, the Cincinnati Gas and Electric
Company and subsidiary systems sustained an interruption to about 40,000 customers and 48,000 kilowatts of
load in the Cincinnati, Ohio and Covington, Kentucky
areas for periods ranging from about thirty minutes to
more than six hours.
The trouble started from what appears to have been
willful damage to a 13 kilovolt cable on a highway bridge
across the Ohio River between the West End Generating
Statian and Covington. This was followed by a pothead
failure on a voltage regulator in the outdoor substation
at the West End Plant, and fire affecting the oil circuit
breaker control cables.
At 6:30 a.m. on May 27, the control cable fire still persisted and it became necessary to deenergize all incoming
circuits to the substation. This resulted in dropping the
Cincinnati downtown network for 5 hours and 20 minutes
affecting about 6,500 customers in a one and one-half
square mile area.
A power interruptiun of 696 megawatts occurred on
May 11 affecting all of the load of Gulf States Utilities
Company in Texas except for a very small area east of
Doucette. Service to 163,000 customers was interrupted.
About half of the severed load was industrial. Interruption was caused by the failure of a lightning arrester
which in turn damaged a bushing on the high voltage side
of a 500 megavolt-ampere transformer at the Sabine
generating station and resulted in tripping out a 440
megawatt generating unit at the station. Five minutes
later, a wave trap burned out interrupting one of two
138-kilovolt lines moving power from Louisiana to Texas
and sequentially causing the second line to open. Within
eight minutes, electric service to the entire Texas area of
Gulf States failed except for the area noted above which,
at the time, was connected only to Louisiana. Service was
completely restored in about seven hours. There was no
secondary damage to the company’s electrical equipment.
At 10: 15 a.m., EDT, an interruption affected approximately 13,000,OOO people and 10,000,000 kilowatts of
load in Pennsylvania, New Jersey, Maryland, and Delaware. The interruption was caused by a short circuit on
a heavily overloaded 230 kilovolt transmission line carrying power from the lower Susquehanna River to Philadelphia. This was followed by automatic tripping of 430,000
kilowatts of generation at the new Muddy Run pumpedstorage project and the subsequent tripping of other lines
and loss of generation. Power was restored after periods
ranging from about one to ten hours.
Attempts to operate remotely controlled switches to
shift some of the load to an adjoining system were
unsuccessful and a partial system interruption
resulted.
In July, 1966, when the Southern California Edison Company lost the entire output of a generating
station ( 1,465,OOO kilowatts) ) amounting to about
25 percent of total system generation, ties to adjoining systems became over-loaded and opened.
Collapse of the Company’s system was prevented
by automatic load-shedding through the action of
under-frequency relays which performed exactly
as intended. Although installed in 1960, this was the
first occasion in which these relays were brought
Pennsylvania - New
jersey - Maryland Interconnection,
June 5,1967
23
\
into action. This interruption is a noteworthy example of the value of load shedding as an emergency measure.
One of the principal cascading power failures of
recent record occurred January 28, 1965, prior to
the Northeast failure, and affected most of the utilities in Iowa and parts -of five other mid-western
States. In many respects, this failure was similar to
the one in November 1965, in the Northeast. It affected a larger area but considerably fewer peopleapproximately two million compared to 30 million
in the Northeast. Service was restored within two
and one-half hours. This interruption was initiated
by a loose connection in a protective relay circuit at
the federally-owned Fort Randall power plant in
South Dakota. The relay disconnected six generators at this station resulting in a loss of 240 megawatts. It also opened all lines into the substation at
the plant. Loss of these lines caused widespread instability of the network, isolation of various areas,
and a general collapse of power operation in the sixstate area. A similar cascading interruption occurred in this same area in June, 1962-also from
the m&operation of a relay at Fort Randall.
Five electric power disturbances occurred on
June 7, July 12, 18 and 2 1 and August 1, 1966, on
the Western Interconnection. The Western Interconnection includes investor-owned and publicly
owned interconnected electric systems in the 11
western states. The five disturbances resulted in
losses of power loads ranging from 312 megawatts
to 975 megawatts, for varying periods up to 45
minutes. Each was of a cascading nature and
resulted in separating the Interconnection into a
number of isolated areas. These disturbances were
unnoticed by most of the people in the area, since
most of the loads interrupted were those of industrial customers.
A number of power failures have occurred on systems which are adjacent to the utilities which serve
most of Texas. The Texas utilities are interconnected among themselves, but not with the bordering systems. This absence of interconnections has
contributed to a number of power failures: near
Sweetwater, Texas, on August 10, 1964 ; at El Paso,
Texas, on December 2, 1965 ; at Beaumont, Texas,
on December 6, 1965, and again at Beaumont on
May 11,1967.
PJM Power Failure, June 5, 1967
A 10 million kilowatt cascading power failure occurred on a major part of the area served by the
24
POWER FAdRE IN THE
PJM INTERCONNECTION
June 5, 1967
Generalized Area of Outage
FI~URB 7
Pennsylvania-New Jersey-Maryland interconnected
utilities (PJM Interconnection), beginning at 10: 16
a.m. on June 5,1967. Spreading across 15,000 square
miles in eastern Pennsylvania, New Jersey and
the Maryland-Delaware peninsula (see figure 7),
the interruption .affected about 13 million people
and lasted for periods varying from one to ten
hours. Service was 70 percent restored by 3 : 00 p.m.,
90 percent by 5: 00 p.m., and to all areas by 7: 55
p.m.
The failure was similar in many respects to the 1
Northeast failure of November 1965. It began ;
with the interruption of an overloaded 230 1
kv line which was transmitting power to Philadel- 1
phia from hydroelectric generating plants on the E
lower Susquehanna River. The interruption, by
prearrangement of system controls, simultaneously
disconnected the full power output of the new
Muddy Run pumped storage project on the Susquehanna River. The four units of the plant at the
time were generating 430 megawatts.
The exact sequence of further line openings and
1
loss of generating plants in the area has not yet been
clearly defined. It appears, however, that the initial 1
incidents precipitated very abnormal system conditions causing numerous additional line segments
and some generating units to trip out of service
over a period of about two minutes. By 10: 18 a.m.,
the automatic inflow of power into the distressed
area from neighboring systems, backed by systems
throughout the nation, reached 1500 megawatts. At I
that time, some of the in-feeding lines became overloaded and opened, creating an electric island.
Power gc
after the
minutes
the time
area had
The 1
to restor
Ph ia in
its hydr
generati
power tc
prompt
delays 1
were ha
ing uni
island 1
develop
a seconc
Basic
adequal
In’
Mlabu
b
WVLLANI
ELECTRIC
lLLUHlNAllNG
I
;
iAl
Power generation in the island began to fail rapidly
after the loss of tieline support, and within five
minutes all generation in the island ceased. At
the time of total failure, frequency in the separated
area had declined to 52 cycles per second.
The Philadelphia Electric Company was able
to restore power in the downtown area of Philadelphia in a little less than one hour. It reconnected
its hydroelectric resources and rebuilt its steam
generation without particular difficulty and restored
power to load blocks in its service area in relatively
prompt sequence. Most other PJM systems experienced some difficulty in restoration. There were
delays for rebuilding boiler pressures, and some
were hampered by temporary damage to generating units. Restoration of power in a part of the
. island was further delayed when local instability
developed as loads were being reconnected, causing
a second loss in generation.
Basically, the failure occurred betause of inadequate transmission, not only within the PJM
Interconnection, but in the ties of the Interconnection to surrounding systems. The tie between
PJM and southeastern New York which opened on
Nov. 9, 1965, again opened on this occasion because
of inadequate capacity. The failure occurred on the
eve of energizing part of a new 500 kilovolt transmission system extending east and west across Pennsylvania and on the eve of the initial operation of a
900 megawatt generating unit, the first of two identical units being constructed at the Keystone Station
in western Pennsylvania. By greatly accelerated
effort, a segment of the 500 kilovolt system was made
ready and energized on June 11, and the initial unit
of the Keystone plant was placed in service under
very light loading on June 18.
The line which failed was a 50 mile segment of
the 230 kilovolt network extending from the Nottingham substation near the Susquehanna River to
Plymouth Meeting near Philadelphia. Through an
inadvertency, the line became more heavily loaded
than planned. Under an interim program to secure
MAJOR TRANSMISSION LINES
OF THE PJM INTERCONNECTION
Including Significant lines (230 KV and Above) in Service at 10~00 AM June 5, 1967
and lines Scheduled for Service by December 31, 1967
from’ one to ten
NIAGARA MOHAWK
lCLEVE
ELECT
IllUMlNAl
overloaded 230
wer to Philadel-
i
IALLEGHENY WWER SYSTEMI
\
’
-. . . I
((
IALLEGHENY
LEGEND
lines became overelectric island.
0
GENERATING STATIONS
A
SUBSlAllON & SWITCHING STATIONS
- 500 KV LINf
- 230 KV LINE
-- fUTURE LlNf SCHEDULED FOR SERVICE
BY DEC 31 1967
MANY GENERATING SIAMNS ARE NOT SHOWN
IVIRGINIA ELECTRIC
a-
FIGURE 8
25
the advantage of power from the new Muddy Run
project prior to placing the 500 kilovolt system in
service, the 230 kilovolt line was scheduled to carry
power only from the Muddy Run project. That part
of the power from the Conowingo Project which had
been carried on the Nottingham line when only two
units of Muddy Run were operating, was to be
transferred to another 230 kilovolt line assigned to
carry all of Conowingo’s generation. By error, however, the Nottingham line continued to carry a part
of the Conowingo load in combination with the full
output of the four units at Muddy Run. The opening of the line occurred when the long spans of the
line sagged physically as the temperature of the
overloaded conductors increased. At about midway
point of the line, one of the three conductors of
the circuit came in close proximity to a 4,000-volt
distribution line which crossed underneath, resulting
in a flashover and fault which caused both the highvoltage and distribution lines to open.
With the exception of two utilities, none of the
PJM systems was equipped, on June 5, to shed loads
automatically. At the beginning of the disturbance
on the morning of June 5, the central dispatch office
of the PJM Interconnection started calls to order
a 5 percent voltage reduction on all PJM systems, a
procedure which is occasionally employed and results in about a 2 percent reduction in load. However, only Baltimore Gas & Electric, Potomac Electric, and General Public Utilities received the calls
before the system conditions deteriorated to a point
where it was apparent &at some form of separation
was imminent. A review of the failure reveals that
the attempted relief had little effect, good or bad,
because the failure occurred before any significant
reduction could be effected. Although all PJM system operators have instructions to shed loads
manually when system frequencies decline, no companies took action to do so except for a minor drop of
125 megawatts by one utility. Had automatic loadshedding been available, relays would have temporarily interrupted less than 10 percent of the
load in the island area to bring generating capability
and load demands into quick balance, permitting
very early reconnection of the island area to the
main network. PJM’s spinning and ready reserves
then could have restored service to the interrupted
loads in a matter of 15 to 20 minutes from the start
of the incident. It appears that some of the difficulties and deficiencies which attended the Northeast failure of November 1965 were also present
in the PJM experience.
26
Reporting Power Failures
In order to secure timely and useful information
on significant power failures, the Commission [
amended its regulations in December 1966 (Order 1
No. 33 1) to require all electric utilities throughout
the nation to report any interruption in bulk power
supply which involves transmission facilities of 69 t
kilovolts or above and causes load interruptions of 1
25,000 kilowatts or more for a period in excess of i
15 minutes. If the interruption exceeds 200,000 kilowatts, the utility must report to the FPC by tele- t
phone as soon as praticable.
Through June 12, 1967, fifty-two power interruptions were reported in accordance with Order
No. 331. Seventeen of the failures were caused
I
by natural phenomena and 25 were the result of
equipment failures. Two were triggered by the
t
actions of birds, one by malicious destruction of in- :
sulators, four by human errors, one by malicious
tripping of circuit breakers, and two by small planes
flying into transmission lines. These interruptions
are summarized in table 2 on pages 28 and 29, and
are briefly described in appendix E.
The
of th
Over
help
flashc
avoic
open
mom
of a I
Sh0l-l
Furtl
light
fore!
equil
01
whit
sever
togel
be re
iines.
In
a he:
accu
flash
Summary of Power Interruptions from 1954 to
wher
1966
i
thee
01
In order that a longer term review could be made t
torn:
of the nature and magnitude of interruptions which
have occurred on power systems in the United f r o m
whit
States, information was assembled fro;n various
Atla!
sources on interruptions which have occurred since
effec
1954. A summary of these and their locations are
ing t
presented in appendix E. Although detailed ina ba
formation is meager, the survey presents the gen- 1
tions
eral nature and frequency of interruptions which
Indi:
have affected the supply of electric power for this
rate
la-year period. The list includes only those interthef
ruptions which were sufficiently important to gain
in II
some measure of public notice.
has
It appears that a number of these interruptions
t work
involved transmission network instability and sepaUtilil
ration, the precursor of potential cascading failures. t
Poe
Others were local in nature, affecting load areas
area,
served radially from the network. Fifty-three perSt
cent of the failures were due to storms, 32 percent
majc
to equipment failures, 6 percent to operator errors, I
t
pow1
and 9 percent to other causes.
ston
In the category of weather-caused interruptions,
Ir
lightning is a frequent offender. A lightning stroke
volt;
can cause a very high voltage flashover from con- c been
ductor to conductor or from conductor to ground.
tion:
t
‘ormation
mm&ion
6 (Order
.roughout
ilk power
ties of 69
options of
excess of
,000 kilo: by telejer interth Order
e caused
result of
1 by the
ion of inmalicious
all planes
:rruptions
3 29, and
1954 to
be made
Ins which
: United
1 various
-red since
rtions are
:ailed inthe genns which
r for this
?se intert to gain
rruptions
tnd sepa; failures.
bad areas
wee per! percent
or errors,
,ruptions,
ng stroke
rom con) ground.
The 60 cycle power then follows the ionized path
of the lightning arc in a continuing short-circuit.
Overhead ground wires above the power circuits
help greatly in fending off lightning strokes. If a
flashover occurs, permanent interruptions are
avoided in most instances by the automatic fast
opening and reclosing of circuit breakers. The
momentary opening of a breaker for about a third
of a second permits the arc to be extinguished. The
short interval of line opening is scarcely perceptible.
Further protection is provided at substations by
lightning arresters which divert lightning surges before they reach vital and vulnerable terminal
equipment.
Outages sometimes occur from the effect of wind
which can cause conductors to oscillate and in
severe storms occasionally to swing close enough
together to cause &hovers. These vibrations can
be reduced by installing vibration dampers on the
iines.
In some circumstances, problems may arise from
a heavy buildup of ice on conductors, or from heavy
accumulation of snow on equipment. Frequently,
flashovers occur from conductors whipping together
when ice begins to melt and falls to suddenly unload
the conductors.
Other atmospheric causes of interruptions are
tornadoes, which occur most frequently in a belt
from Texas to the Great Lakes, and hurricanes,
which wreak their destruction primarily along the
Atlantic and Gulf coasts. Probably the most severe
effect of a tornado on power facilities occurred during the night of April 11, 1965. The storm, in effect
a barrage of tornadoes, caused extensive mterruptions of local service from Iowa through Illinois,
Indiana, Ohio and into Michigan. Some 37 separate tornadoes were identified as having affected
the facilities of the American Electric Power system
in Indiana and Ohio. However, the system, which
has developed a strong internal transmission network and has strong connections with neighboring
utilities, was able to reroute power over undamaged
portions to maintain service in almost all of its
area.
Storms are less likely to affect power service in
major metropolitan centers, because most of the
power facilities are underground and protected from
storm damage.
In a few areas subject to frequent storms, high
voltage transmission facilities above ground have
been especially designed to withstand storm conditions. Utilities in Florida, for example, have success-
fully employed a “hurricane proof” design for highvoltage transmission lines. Many storms, however,
cause damage and local interruptions, even though
special protection is provided for high voltage transmission facilities.
Although it is not possible to prevent direct ,damage to equipment and transmission lines from severe
weather phenomena, transmission systems can be
planned, as exemplified by the continuity of bulk
power service on the American Electric Power System despite extensive tornado damage, to prevenr
localized damage from causing a widespread power
failure.
Interruptions Avoided
A power interruption is immediately obvious to
the general public, but the instances in which interconnections assist in preventing interruptions go
unnoticed. Few people are aware of the frequency
with which sudden outages occur in major generating and transmission equipment. In most cases the
automatic and instantaneous rerouting of power
over the network to points of need prevents an interruption in service. A number of instances have
occurred in recent years in which the amount of
power suddenly lost has approached the magnitude
of the initial surge which started the Northeast
failure of November 9. Some instances of disturbances which probably would have caused interruptions to service except for the support afforded by
the system’s own network or through its interconnections with other utilities are described below.
The information was assembled by the Commission’s Regional Advisory Committees.
A study of the Pennsylvania-New Jersey-Maryland Power Pool (PJM) discloses that on 129 occasions since 1955, a unit, and in one case, two
units, tripped off with a loss in generation to the
system of 200 megawatts or more. In the most extreme case, the unit lost represented about 67 percent of the owning system’s load at the time. PJM’s
intra-pool and inter-pool connections replaced the
loss of generation, and in no instance was customer
load interrupted or curtailed.
The Southeast Region reported a total of 57 incidents between January 1, 1964 and June 30,1966,
involving equipment outages totalling 12,397,OOO
kilowatts, or an average of 218,000 kilowatts per
outage. Seven outages of about 500,000 kilowatts
were reported. In only one of these incidents was
curtailment of load required.
27
TABLE Z-Power service intmupfions reported in
amwdamc with
-iUtility
Date
1967
Location
--
1-15
1-16
l-24
l-25
l-26
l-26
l-28
2- 2
2- 8
2- 9
2- 9
2-15
2-17
2-20
2-24
2-25
2-25
2-27
2-28
3-6
3-10
3-10
3-12
3-14
3-16
3-19
* 3-19
3-26
3-27
3-27
3-27
3-28
3-28
4-12
4-13
4-16
4-19
4-20
5 - l
5 - l
5-8
5-11
5-12
5-12
5-17
5-19
5-25
5-26
6-2
6-5
6-9
6-12
Marias River Electric Coop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MoreauGrandElectricCoop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
UnionElectricCompany . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ProvoMunicipal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Grand River Dam Authority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Illinois Power Company . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ElPasoElectricCompany . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fulton, Ky., Municipal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tennessee Valley Authority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ChugachElectricAssociation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Moreau Grand Electric Coop. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OhioEdisonCompany . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Public Service Co. of Indiana. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Burbank Municipal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Carolina Power d Light Co. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tennessee Valley Authority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ariiona Public Service Co . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GeorgiaPower Company . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Texas Power d Light Company . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Duquesne Lighting Company. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pacific Power &’ Light Co . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tennessee Valley Authority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Moreau Grand Electric Coop. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Western Interconnection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sacramento Municipal Utility Dist. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Grand River Dam Authority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sherrard Power System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Marquette Bd of Lt B Pwr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pacific Power 63 Light Co . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tennessee Valley Authority. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Georgia Power Company . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Utah Power.@ Light Company. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Puget Sound Pwr. d Lt. CO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bangor HydroElectricCo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Jefferson Davis Elect. Coop. Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Muscatine Iowa Municipal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bailey County Elect. Coop. Assn. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Western Interconnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Community Public Service Co. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Carolina Power & Light Co. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
South Carolina Electric &’ Gas Co . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gulf States Utilities Co. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Virginia Electric 133 Power Co . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Greenville Texas Municipal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cleveland Electric Illum. Co . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
South Texas Electric Coop. Inc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bonneville Power Administration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cincinnati Gas 6? Electric Co. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SnohomishCounty PUD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PJMInterconnection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Utah Power & Light Co. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pennsylvania Power d Light Co. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
Shelby, Montana. . . . . . . . . . . . . . . . .
Timber Lake, S.D . . . . . . . . . .
St. Louis County. . . . . . . . . .
Provo, Utah. . . . . . . . . . . . . . .
Oklahoma. . . . . . . . . . . . . . . . .
Champaign-Urbana . . . . . . . .
ElPaso,Tcxas . . . . . . . . . . . .
Fulton, Kentucky . . . . . . . . . .
Bowling Green, Ky . . . . . . . . .
Anchorage, Alaska. . . . . . . .
Timber Lake, S.D . . . . . . . . . .
Massillon, Ohio. . . . . . . . . . . .
Batesville, Ind . . . . . . . . . . . . . .
Burbank, Calii. . . . . . . . . . . .
Asheville, N.C . . . . . . . . . . . .
Johnson City, Tenn . . . . . . . . .
S. W. Arizona . . . . . . . . . . . . .
Fulton-Cobb Cntys. . . . . .
Grayson B Adj Cntys. . . . . . .
Pittsburgh, Pa.. . . . . .
..
Crescent City, Cal. . . .
Bowling Green, Ky .
..
Timber Lake, S.D. . . .
.
.
Washington-Colo . . .
..
Sacramento, Calif..
.. ...
Oklahoma. . . . . . .
...
.. ...
Orion, Illinois. . . . .
Marquette, Mich. . . . . .
Enterprise, Ore . . . . . . . . . . . . . . . . .
..
Mayfield, Ky . . . . . . . . . . . . . . .
Marietta, Ga. . . . . . . . . . . . . . . . . . .
Southeast Utah . . . . . . . . . . . . . . . . .
East Seattle, Wash. . . . . . . . . . . . . . .
Veaaie B Vincent, Maine. . . .
.
Cameron Parrish, La. . . . . . . .
Muscatine, Iowa. . . . . . . . . . . .
..
Muleshoe, Texas. . . . . . . . . . . .
.
Washington tY Idaho. . . . . . . .
Princeton, Texas. . . . . . . . . . . .
Rocky Mount, N.C. . . . . . . . . . .
.
Charleston, S.C . . . . . . . . . . . . . .
.
Beaumont, Texas. . . . . . .
Richmond, Va. . . . . . . . .
Greenville, Texas. . . . . . .
Cleveland, Ohio. . . . . . . .
Corpus Christi, Texas.
Spokane, Wash. . . . . . . . .
Cincinnati. Ohio.
Everett, Wash. .
Pa., N.J., Md., Del.
Salt Lake City, Utah.
Frackville, P a . . .
-
* Not Reported
28
.
.
E
115 kv USBF
High windsTornado.. . .
Line short-l
Lighting arre
Icing-high 1
Bii nest on I
Lightning. . .
Current tran
Arcing horn :
Line pin cam
Construction
Transformer
Lost 55 mw I
Broken insul;
Transformer
Plane hit 69 1
Ground wire
Disconnect s\
Flood-lost I
Wet, heavy s:
Current tram
Icing on 69 k
Overload due
High wind-.
X-arm Failec
Insulator co*
Broken insul;
Insulators shz
Bird shorted i
115 kv condu
Water leak tr
Cable or pod
Flash over on
Salt spray COI
Tree feIl on t
Insulator fail
Line tripped
Wind and lig
Not determiu
Tree fell on 1
Insulator fail
Lightning an
Generator exl
OCB’s openeq
Unexplained
Crop dusting
13 kv cable E
Brushfire...
Operating en
Not reported
Lightning an
w rcfiorted in
accordance with FPC Order .No. 331 through June 12, 1967
.Cause
MW Los
1
Customers
Duration
HI%
-
..........
..........
..........
..........
..........
..........
..........
..........
..........
..........
..........
I:. . . . . . . . .
i--*-*-.........
..........
..........
..........
..........
..........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
-
115 kv USBR line fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
High winds-galloping conductors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tornado . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..
Line short-falling snow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lighting arrestor failure. : . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Icing--highwinds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bii nest on substation bus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lightning.................................: .................... .
Current transformer failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Arcing horn failure on switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Linepincameout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Construction material blew into substation. . . . . . . . . . . . . . . . . . . . . . . . . . .
Transformer tap changer failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lost55mwunitduetoLosAngelesfault.. . . . . . . . . . . . . . . . . . . . . . . . . .
Broken insulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transformer tripped, over temperature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Planehit69kvline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ground wire fell on 115 kv line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disconnect switch insulator broke . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Flood-lost Elrama Generating Sta. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Wet, heavy snow on 120 kv line. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Current transformer failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Icingon69kvline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overload due to switching. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
High wind-jumper burned off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
X-arm Failed-Pole caught fire. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Insulator contamination. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Broken insulator..............................................~ . .
Insulators shattered by gun shots. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bird shorted insulator. . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . .
115 kv conductor burned at clamp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Water leak tripped 138 kv circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cable or pothead failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Flash over on 46 kv-loose connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Salt spray contaminated insulators-69 kv. . . . . . . . . . . . . . . . . . . . . . . . . . .
Tree fell on 69 kv line-lost 56 mw plant. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Insulator faileddross arm burned. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Line tripped while BPA was installing relay. . . . . . . . . . . . . . . . . . . . . . . . . .
Wind and lightning tripped 138 kv line. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Notdetermined . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tree fell on 115 kv line-lost substation. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Insulator failures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lightning arrestor failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Generator exciter failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OCB’s opened manually. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unexplained differential relay operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Crop dusting plane damaged line. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13 kv cable failure and fire in generating station. . . . . . . . . . . . . . . . . . . . . .
Brushfire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Opvatingerror . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Notreported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Lightning arrestor failure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E
Min.
-
7.0
4.0
75. 0
15. 0
30.0
30.0
25.0
1.0
64.0
37. 5
2.0
50. 0
28.0
10. 0
27.0
37. 6
25.0
56.0
30. 0
120.0
28.0
50.0
2.0
282
50. 0
30.0
10. 3
10. 5
5. 0
52.0
23. 8
35. 0
45. 0
35.2
6
27
9
10.11
9
25
38
700
38
23
80
14.6
31
48
60
), 300
105
163
2,900
2, 708
75, ooo
12, ooo
2
17,000
N.R. *
1, 648
N.R.’*
18, 100
2,500
20, ooo
6, 182
3, ooo
16,000
Johnson Cy
4,500
20, ooo
18, 000
8
6, ooo
2
2, 200
50, ooo
37,748
2
5, ooo
8,500
2,500
25, 000
N.R.’t
8,400
22, ooo
42,000
2, ooo
8, ooo
NR* I:
NR3 c
3, 140
1
15,080
163,008
12,508
9, 108
66, ooo
17,135
SCW.d
thousand
4QfJOQ
15,000
13,000,080
NR*
78,000
- 03
31
1
16
1
25
30
20
30
15
35
20
04
15
20
35
33
22
52
36
29
43
30
36
16
18
13
24
23
25
53
50
32
59
50
20
27
27
23
30
00
a
8
a
a
1
a
1
0
0
0
1
0
0
0
0
4
3
0
1
0
0
9
1
0
6
0
0
0
0
0
3
2
1
NR *
1
0
0
6
0
3
0
0
1
__ J
-
I
l.?--
’
02
59
16
22
24
20
28
50
16
00
29
30
15
24
I
-
29
The West Central Region indicated a total of
170 incidents between January 1, 1964 and
June 20, 1966. Over 90 of these outages exceeded
100,000 kilowatts and several exceeded 500,000
_ . *kilowatts. For example, Commonwealth Edison
---%mpany had four incidents during this period
when one of its 580,009 kilowatt units tripped out
of service while carrying full load. Records of one
occasion indicate that over 95 percent of the loss
was supplied by Commonwealth’s neighbors
through interconnections. No transmission lines
opened and no customer load was dropped.
The East Central Region reported 13 1 equipment
outages during the 2ya year period from January 1,
1964 through July 1, 1966, without any loss of
customer load.
The South Central Region reported a total of
236 incidents between January 1961 and August
1966, involving generating unit interruptions with- ’
out any loss of customer load.
t
The credit to interconnections in the instances
reviewed is not necessarily limited to preventing a
loss in load equal to the loss in capacity of generating equipment which failed. Without the support
F
of an adequate network, some of the outages might
well have led to large system-wide or area-wide
failures.
Ct
1I
Compositic
In the di\
tion, the UI
unique amor
3,500 system
,
Nor&east Rq
Investor-ow
Public (non
Cooperative
F&d....
Total..
East Central
Investor-ow
Public (non
Cooperativl
Federal..
Total.
Southeast Re
Investor-ov
e.
t
Public (no1
Cooperativ
Federal.
Total.
South Centri
Investor-01
Public (no:
COOpuati\
Federal..
Total.
1 Include
I
1
y loss of
a total of
nd August
tions with-
i
)e instances
mventing a
1 of generatihe support
pages might
I area-wide
CHAPTER 4
COMPOSITION, INTERCONNECTION AND COORDINATION OF
ELECTRIC SYSTEMS
Composition of the Industry
In the diversity and complexity of its organization, the United States electric utility industry is
unique among the power systems of the world. Over
3,500 systems, varying greatly in size, type of ownership and range of power supply functions, participate in the generation, transmission, and distribution of electric energy in the United States.
T ABLE
The industry is made up of four segments according to types of ownership-investor-owned
utilities, state and local public agencies, cooperatives, and Federal agencies. Data on the size, number of systems, functions, and energy requirements
of each segment are tabulated by regions for the
contiguous United States in tables 3 and 4.
Figure 9 illustrates the geographic distribution of
3.-Regional distribution of electriG utilities-Z965-By function
Number of Systems
Number of Systems
Ownership
Engage in
Generating and
Transmission
Engage in
Distribution Only
111
182
31
9
63
54
3
9
48
128
28
0
Total . . . . . . . . .
East Central Region:
Investor-owned. . .
Public (non-Federal).
Cooperatives . . . .
F e d e r a l . .
333
129
204
54
256
108
0
33
95
5
0
21
161
103
0
Total. . . . . . . . . .
Southeast Region: ’
Investor-owned. . . .
Public (non-Federal). .
Cooperatives. . . . . .
Federal.
.
.
418
133
285
40
324
194
4
27
33
9
3
13
291
185
1
Total. . . . .
South Central Region:
Investor-owned. . . . .
Public (non-Federal).
Cooperatives. . . . . . . .
Federal. . . . . . . . . . . . .
562
72
490
53
381
201
6
34
154
13
6
19
227
188
0
Total. . . . .
641
207
Total
Northeast Region :
Investor-owned. .
Public (non-Federal).
Cooperatives. . . .
F e d e r a l .
Total
West Central Region:
Investor-owned. . .
Public (non-Federal). .
Cooperatives. . . . .
Federal. . . . .
Sngage in
Generating and
Transmission
Sngage in
Distribution Only
.
.
.
.
85
706
272
4
56
300
20
4
496
252
0
Total. . . . . . .
West Region:
Investor-owned. . . .
Public (non-Federal). .
Cooperatives. . . . . . .
Federal...............
1,067
380
687
94
252
165
18
49
89
22
17
45
163
143
1
Total . . . . . . . . . . . .
Summary for the Contiguous United States:
Investor-owned 1. . .
Public (non-Federal).
Cooperatives. . . . . . . . .
Federal. . . . . . . . . . .
T o t a l s .
1 Includes 20 industrial concerns that supply energy to customers.
.
.
29
352
262
725
72
39
175
1,376
899
2
1,098
2,452
T ABLE 4 .-Regional distribution $‘clcctrk utilities-1965-by size of entrgy requirements
Annual Energy Requirements, Billions of Kwh
I
ownership
-z-Over 10
0.1-l .o
1.0-10
Jnder 0.1
-Northeast Region:
Inv*ltor-owned . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Public (non-federal) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cooperatives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Federal Government. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
111
4
0
0
0
22
1
0
0
18
14
1
0
67
167
30
9
Total Number of Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . .
East Central Region:
Investorswned . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Public (non-federal) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cooperatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
FederalGovernment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4
23
33
273
7
0
0
0
19
1
0
0
8
14
3
0
20
241
105
0
Total Number of Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Southeast Region:
Investor-owned . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Public (non-federal). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cooperatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Federal Government. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7
20
25
366
418
6
0
0
1
8
7
0
2
3
74
37
1
23
243
157
0
40
324
194
4
7
17
115
423
2
0
0
0
19
4
0
1
9
16
12
1
23
361
189
4
Total Number of Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Weat Central Region:
Investor-owned . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Public (non-federal). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Coopffatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Federal Government. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2
24
38
15
2
1
1
22
13
17
2
46
691
254
1
272
4
Total Number of Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . .
West Region:
Investor-owned . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Public(non-federal) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cooperativei . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Federal Government . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2
19
54
992
1,067
14
9
0
2
18
44
18
5
60
198
147
10
94
Total Number of Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Summary for the Contiguous United States:
Investor-ownedl.....................................
Yublic (non-federal). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cooperatives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ftderal.............................................
4
25
85
415
23
1
0
2
97
24
1
6
78
175
88
9
239
1,901
882
24
Total number of systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
26
128
350
Total Number of Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . .
South Central Region:
Investor-owned . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Public (non-federal) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cooperatives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fe&&Government . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 Includes 20 industrial concerns that supply energy
32
to customers.
Of
and t
quire
large]
Total
- - - 182
outp1
31
stanti
cilitie
tram1
with
kilow
9
333
t
= Ec
watts.
.S
t
252
165 t
1 8
f
529
Rl.
!
i
67
167
111
182
30 9
31 9
-I
273
c
333
20
241
54
256
105 0
108 0
366
418
23
243
157
0
40
324
194
4
Ii i
systems in each of the four segments. The boundaries of the six regions listed in tables 3 and 4 are
shown in figure 10.
Of the 1,100 systems that engage in generation
and transmission, only 154 have annual energy requirements in excess of one billion kwh, but these
larger systems produce more than 90 percent of the
output of the electric power industry and own substantially all principal bulk power transmission facilities. More than half of the 1,100 generating and
transmission systems are small municipal systems
with energy requirements of less than 100 million
kilowatt-hours per year.22 At the present time, many
22 Equivalent to a system peak of 20,000 to 25,000 kilowatts.
of these small systems and a few of the larger systems, such as the Columbus and Cleveland municipal systems in Ohio, are electrically isolated.
More than two-thirds of the electric utility systems in the nation, mainly small municipal and cooperative systems, engage only in the distribution of
electricity. Many of the 899 distribution cooperatives are members of generating and transmission
cooperatives (G&T’s) and thereby participate indirectly in the generation and transmission functions. A substantial number of the 1,376 public
(non-federal) systems that are engaged only in distribution are supplied partially or entirely with
power produced at Federal projects or by public
power entities such as the Power Authority of the
SERVICE AREAS OF ELECTRIC UTILITY INDUSTRY
In the 48 Contiguous States
INVESTOR-OWNED UTILITIES
NON-FEDERAL PUBLICLY OWNED SYSTEM
(Municipal,State,Countv.and
Power Districts)
562
23
361
189
4
53
381
201
6
641
1i
46
691
254
1
85
706
272
4
.SINGLE UTILITY SYSTEM
SINGLE MUNICIPAL SYSTEM-LIMITS OF SERVICE AREAS
OF STATE POWER AUTHORITIES AND UTILITY DISTRICTS
ORGANIZED UNDER STATE STATUTE DEFINED BY SHADING
l
1,067
’
I
60
198
147
10
94
252
165
18
RURAL ELECTRlC COOPERATIVE SYSTEMS
FEDERAL MARKETING AREAS
415
i
239
1,901
885
24
-j
-
From 1964 National Power Survey
FICXJRE 9
33
State of New York. Much of this power, except in
the TVA area and to a large extent in the Pacific
Northwest, is wheeled over the facilities of the investor-owned companies. Most of the remaining
distribution systems purchase their entire requirements from investor-owned companies.
Interconnection of Utilities
The framework of interconnections has changed
materially since 1939 when the electric power industry of the United States was divided into numerous relatively small groups of interconnected systems. The progression of interconnections from
1939 to today’s pattern of nearly complete interconnection throughout the country is depicted on
figure 11. The most recent joining of areas occurred in February, 1967, with the closure of four
transmission lines in the west to tie together electrically the eastern and western grids.
Although the great majority of the nation’s power
systems are now interconnected in a single network,
the network is not strong enough at many points to
assure adequate support in the event of emergency.
Some inter%onnections are, in a sense, round about
and others can do little more than maintain the
\JL-
areas which they join in synchronous operation
under normal conditions; many tie lines have insufficient reserve capacity for superimposed emergency loads. Until very recently, for example, the
systems in the northwest were not interconnected
with those in the southwest except indirectly
through Idaho, Wyoming and Utah, an interconnection of very limited strength. Similarly, tie-line
capacities are very limited between the southwest systems and the south central areas; between
northern New Mexico and El Paso, Texas; from
the northwest to the north central states; and from
the Upper Missouri River Basin to systems in Nebraska. The four ties mentioned above as interconnecting the eastern and western grids are of limited capacity. Most utilities serving areas entirely in
Texas still have no operating interconnections with
neighboring areas across state lines. Systems in
Michigan za are interconnected with the main net28 The principal Michigan systems (Detroit Edison Company and Consumers Power Company) have entered into
an agreement with systems in Ohio and Indiana for the
construction of two 345-kv interconnections betwee,n the
two groups, expected to be completed on or before January 1, 1970.
NATIONAL POWER SURVEY REGIONS
-,
FEDERAL POWER COMMISSION
POWER SUPPLY AREA
REGIONS SELECTED FOR UPDATING
THE NATIONAL POWER SURVEY
FKXJRE 10
GROWTH OF INTERCONNECTED SYSTEMS
OPERATING IN PARALLEL
mous operation
e lines have inz-imposed emer‘or example, the
t interconnected
xcept indirectly
ah, an intercon,imilarly, tie-line
reen t h e southI areas; between
so, Texas; from
states; and from
o systems in Nemove as intercongrids are of lim; areas entirely in
,connections with
ines. Systems in
.th the main net-
1962
/etroit Edison Com-
1967
j have entered into
nd Indiana for the
dons between the
i on or before Jan-
BOUNDARIES OF INTERCONNECTED
SYSTEM SERVICE AREAS (Generalized)
UNSHADED AREAS INDICATE LOCAL SERVICE ONLY
FICWRE 11
work of the U.S. only through the network in Ontario, Canada. Deficiencies in network strength in
the northeast have already been discussed. Elsewhere in the east, networks need strengthening in
western Pennsylvania and in parts of the PJM
area, and between systems in Florida and areas to
the north.
Coordinated Planning and Operation
Various arrangements for coordinated planning
and operation have been worked out among some
of the interconnected systems. The most comprehensive form of coordination is the formal power
26’7-781 O-674
pool under which two or more systems coordinate
their resources in varying degrees for the supply
of their combined loads under a contractual arrangement. The 18 major formal power pools now
in existence are depicted on figure 12. Membership
in these pools and in the principal planning groups
outlined in figure 13 are listed in appendix C.
Bulk power supply reliability and optimum
economy are not automatically assured by the establishment of a formal power pool. Members must
participate jointly in planning and operation of
pool facilities and provide transmission ties that
have ample reserve margins to operate within safe
35
MAJOR POWER POOLS
metn
lmas
ghen
COO1
ber I
whit
coor
T:
inch
inter
min
agre
lant
to ir
Cool
mer
pati
StZil
P
the
fun
sew
(Ii) Denotes Holdtng Company Peal
Q Denotes a pod formed sim 1960.
Note Pow PC& shown are hmtted to those
ast&M under formal arrangements.
FIGURE 12
and stable limits under emergency conditions as
well as during normal loading. Maximum benefits
are achieved when power pool members plan new
generation and transmission facilities and operate
these facilities as though the entire power pool were
a single electric system.
Benefits of Coordination
Many benefits are available to member systems
of fully coordinated power pools. For example, less
total installed capacity is needed because of peak
load diversity, diversity of forced outages, balancing
of load forecasting errors, coordinated planning of
capacity additions, and diversity in schedules for
unit maintenance. Operating costs are reduced by
centrally dispatching power from the most economical sources of the pool. Greater reliability can be expected through the pooling of generation and transmission resources, and through the pooling of talent
to study network stability, develop sound transmission and control systems, determine operating
limits, and program spinning and standby reserves.
The PJM Interconnection
The Pennsylvania-New Jersey-Maryland Interconnection (PJM) is an example of a formal
36
Tb
cltl
era
sub
pez
power pool which has gone far toward establishing a mechanism for useful coordination. This pool
consists of six full members including one holding
company with four operating subsidiaries. In addi01
tion, PJM has three associated systems which par. . .
ticipate in many of the coordinating functions. The
O t l
members of PJM coordinate the planning of new
I
hti
generation and transmission facilities. They operate
of
the existing facilities with free flowing ties as though
an
PJM were a single electric system. The service area
ab
of the PJM utilities and the major transmission lines
sin
of this interconnection are shown in figure 8,
co
page 25.
VI
Each member in PJM is responsible for providing
ar
capacity to meet its own loads plus its proportionate
en
share of total required system reserves. New generash
tion is scheduled taking into consideration the retic
sults of joint planning with the objective that total
pool capacity will be adequate to meet total load and
reserve requirements. All generation is dispatched
under central control. Capacity and energy transactions are accounted for after the fact with savings shared equally among the parties to each
bl
transaction.
ai
At present, coordination between PJM and neigha:
boring groups is accomplished through agreements
between the members of PJM and one or more
1 establishI. This pool
me holding
zs. In addiwhich parctions. The
ing of new
hey operate
:s as though
service area
nission lines
I figure 8,
r providing
Dportionate
lew generaion the ree that total
al load and
dispatched
ergy transt with saves to each
and neighagreements
le or more
!
members of the New York Power Pool, the Carolinas-Virginia Power Pool (CARVA), the Allegheny Power System, and the Central Area Power
Coordination Group (CAPCO) . Each PJM member receives some portion of the financial benefits
which result from transactions under each of these
coordination agreements.
The PJM agreement permits pool members to
include the loads and resources of associated systems
interconnected with them for the purpose of determining pool transactions. This provision of the
agreement permits associated systems such as Atlantic City Electric and Delmarva Power & Light
to improve system reliability and economy through
coordinated planning and operation with pool
members. These two associated systems are participating in the 1,800 megawatt Keystone Generating
Station.
Although the P JM pool has increased its role over
the years in coordinating the planning and operating
functions of its members, it currently suffers from
several of the difficulties that are affecting the reliability of bulk power supply in a number of areas.
These problems, briefly reviewed in chapter 6, include delays in the scheduled start-up of new generation and energizing new transmission, which has
substantially reduced reserve margins for meeting
peak loads this summer ( 1967).
Other Forms of Coordination
In addition to the formal power pools, many
other, less comprehensive, coordinating mechanisms
have been developed. Among these are a variety
of agreements under which systems exchange power
and energy to achieve improved economy and reliability of power supply. Such contracts range from
simple emergency assistance agreements to highly
complex arrangements for the exchange of various
types of electric services. Another coordinating
arrangement of growing’importance is the joint
enterprise in which several entities join in the ownership of a single generating plant or both generation and transmission facilities.
Various organizations have been formed to engage in inter-system planning on an area or regional
basis. The work of these groups is generally carried out by committees composed of representatives
of the several members Some of these groups have
been successful in developing comprehensive plans
and constructing bulk power facilities on a large
area or regional basis.
Several new organizations intended to encourage
some degree of coordination have been established
or announced recently. One of these, the Northeast
Power Coordinating Council, has been discussed in
chapter 2. In February, 1967, it was announced that
a Reliability Coordination Agreement had been
executed by 23 investor-owned utilities in the East
Central area.24 The stated purpose is “to augment
reliability of the parties’bulk power supply through
coordination of the parties’ planning and operation
of their generation and transmission facilities.” The
agreement, besides providing for a representative
board which will establish principles and procedures
for system operation involving reliability also expresses intentions to study the possibility of additional arrangements that will also contribute to operating economies. The agreement also establishes a
Coordination Review Committee which is charged
with the responsibility for reviewing with each party
to the agreement its plans for generation and transmission facilities and other matters relevant to reliability and to guard against adversely affecting the
reliability of other ECA members’ bulk-power supply. It also establishes a full-time manager to coordinate decisions made by the various operating and
planning committees.
Another procedure for coordinating two or more
interconnected systems is corporate merger or the
formation of a holding company. After merger or
holding company affiliation, management normally
will begin to operate the facilities as a single system
and to plan for new facilities on a single-system
basis. With few exceptions, mergers in recent years
have been in the form of acquisitions of small utilities or parts of utilities by larger systems. The formation of new holding companies has become very
infrequent.
Areas for Improving Coordinating
Organizations
The inventory of existing coordinating groups recently completed by the Federal Power Commission’s Regional Advisory Committees indicates that
some power pools are too small, by themselves, to
** An area including all or parts of the States of Indiana,
Ohio, Kentucky, Virginia, Maryland, Tennessee, West Virgina, Michigan and Pennsylvania and one which approximately corresponds with the area served by the Commission’s East Central Regional Advisory Committee. The
principal exceptions are the systems in Michigan which are
expected to become parties to the Agreement when the
interties across the Indian-Michigan and Ohio-Michigan
borders are completed.
37
take full advantage of large-scale, efficient generating units, and EHV transmission. However, many of
these are attempting to gain the advantages of more
extensive coordination through membership in regional planning organizations which provide opportunities for both formal power pools and individual
systems to participate in joint planning over broad
geographic areas.
The creation of a large number of planning organizations in recent years has resulted in overlapping in some areas as illustrated in figure 13 ; 25
in others there is no regional planning organization
at all. For example, although subsidiary utilities of
the Southern Company, which operate in Georgia,
Alabama, Florida and Mississippi, are well coordinated among themselves, and there is some degree
of coordination among utilities in adjacent Florida,
they do not participate in a common regional coordis The eastern boundary of MAIN (No. 3) has been
changed very recently to eliminate overlapping with
ECARCA (No. 11) .
nating organization.26 Such an orgamzatlon COUICI
help make better use of the available opportunities
for economy, including a seasonal load diversity in
the order of 1,000 megawatts between Florida and
areas to the north.
Continuing Problems
Some of the most challenging problems of successful operation of planning and pooling organizations pertain to ways of reaching accord among the
various members and the resolution of disagreements as, for example, where one or more members
decline to participate in the construction of facilities
which serve the entire area. The formation of planning and pooling organizations has often necessitated assurance to the several members that individual rights and prerogatives will not be overridden
1
IJy
!
I1
I
aa Announcement has been made recently of the formation of an organization comprising the eight electric systems
of the CARVA and Southern System power pools to
enhance bulk power supply reliability in the region.
PRINCIPAL POWER PLANNING GROUPS IN THE UNITED STATES
: : : : : : : : : : 2 Cmtrol Are.3 Pwe, Caxdin.a,ion Grwp
- 3 M,d.Americo l”ferpOOl Ne,*ork
- - - 4 M,d.Cootment Area Power Pionnerr
- 5 Southwest Pow, Pool
FICXIRE 13
I
t
f
IrlaJ”“L)
agreement i
sions which
made for 1
organization
riod of tim
The cone
in that it c
questioned
debate that
time it ma
thwarting t
element ant
to reliabilit
planning a
solution in
utilities is n
rather to I
reasons ant
but these a
teed in act
Small sy!
portunity t
tion with fc
rectly, but
area and rt
pools and
small syste
plete elect
installatior
erating cal
if coordina
generally :
and inferi
The chz
permit int
in emerge
large. Sm:
r coordir
wganization could
able opportunities
J load diversity in
wen Florida and
i
iroblems of sucpooling organizaaccord among the
‘on of disagreeEh
br more members
WYion of facilities
Wmation of planlas often necessibers that individlot be overridden
ently 01 the formaight electric systems
m power pools to
n the region.
iD STATES
by majority vote. As a consequence, unanimous
agreement is often required at least in those discussions which affect all members. Usually, provision is
made for withdrawal by any member from the
organization following notice after a specified period of time.
The concept of unanimity is not without benefit
in that it can be expected to bring to bear, in a
questioned decision, a thoroughness of analysis and
debate that might not otherwise result. At the same
time it may be expensively time-consuming and
thwarting to vital progress. Tie can be a critical
element and delays can be as severe a transgression
to reliability as lack of thoroughness in power system
planning and operation. It would seem that the
solution in the bverall interest of the public and the
utilities is not to sweep aside the minority view, but
rather to recognize the right to object for valid
reasons and to call for further study and analysis;
but these accomplished, planning should then pmteed in accord with the preponderant view.
Small systems usually have not been given the opportunity to coordinate their planning and operation with formal power pools, either directly or indirectly, but recently they have begun to participate in
area and regional coordination as satellites of power
pools and planning organizations. Hundreds of
small systems, however, are still operating in complete electrical isolation. This has resulted in the
installation by many small systems of reserve generating capacity that would not have been needed
if coordination were practiced. Isolated operation is
generally accompanied by higher production costs
and inferior reliability.
The characteristics of electrical networks which
permit interconnected systems to assist each other
in emergencies apply to small systems as well as
large. Small systems participating in power pools
or coordination agreements must expect to carry
their share of responsibilities associated with interconnected planning and operation. Their generating capacity and operating reserves must be maintained and must be operated under standards and
controls which are commensurate in quality with
those of the larger systems. To the extent it may be
physically impossible for a small system to fulfill
all such obligations in kind, equalization should take
the form of exchanging power or dollars among the
systems.
Among the problems of interconnected system
coordination are the equitable sharing of costs and
the division of ownership of interconnecting facilities. Such problems appear to be especially acute
where the systems differ greatly in size and in type of
ownership. No formulae have been accepted as universally applicable to these situations. However,
policies and practices are evolving through discussions and negotiations among utility systems and in
formal and informal proceedings with regulatory
agencies in which a wide range of pertinent factors
are being considered such as relative benefits,
methods of participating, reliability of service, conservation of natural resources, alternative opportunities and broad equities.
Conclusion
Interconnection and coordination of systems has
been progressing steadily in recent years. Some of
the more widespread forms of coordination at the
present time, particularly among relatively large
systems, include interchange arrangements, formal
power pools, joint enterprises and joint planning.
In addition, it appears that the industry is properly
placing growing emphasis on coordinated planning
on a regional scale, partly under the impetus of the
Northeast power failure. These developments are
commendable, but greater progress is essential if the
industry is to keep pace with the multiplying demands for reliable, low-cost power.
*
39
CHAPTER 5
KEY ELEMENTS FOR RELIABILITY IN THE PLANNING AND OPERATION OF
INTERCONNECTED POWER SYSTEMS
Imaginative planning and thorough analysis are
0th key ingredients in engineering of bulk power
Istems. The inherent challenges have attracted a
igh order of technical talents, Opportunities and
aponsibilities presented by the increasing interxrnection and coordination of electric utility sys:ms should stimulate continued attention by creave engineers.
Electric system planning proceeds continuously
nce effective planning must consider tentative
lans for distant needs while at the same time comleting arrangements for the immediate future.2’
loreover, effective planning is intimately tied to
rstems operation. The progress of technology intenfies the systems approach, intrinsic to this industry.
The electric utility industry deals in a unique
nergy process. It produces, from the heat of bumig fuel and nuclear reactions or from falling water,
different form of energy which travels at the speed
F light and must be consumed by the customer
bads as it is produced. Generation must continuusly be equal to load in the operation of power
rstems. The load balance fluctuates continually as
lstomers alter usage, and system balances change
,henever a generator or a part of the transmission
rstem suddenly becomes impaired or is tripped out.
‘he changed requirements can be met very briefly
y stored energy from the electromagnetic fields of
re generators themselves and the mechanical in-tias of the rotating turbines or rotors. Within a
ratter of seconds or less, however, load variations
eed to be matched by variations in the input of
rime energy. The ability of a group of generators
) operate continuously and reliably to meet loads
epends on the capacity of such generators to rexmd rapidly to meet changing needs and on the
istribution of generators and loads throughout the
stem. The ability of the entire system to maintain
RThe Advisory Committee on Reliability has underken an extended treatment of the planning process. See
olume II, Appendix F.
stable operation depends on these factors and the
transmission capacity tying together the various
parts of the network. The stronger the transmission
ties, the better assurance there is that under severe
disturbances generators over a wide area will remain
available to share the load.
Electric system planning identifies and evaluates
alternative bulk power arrangements in terms of
load requirements, reliability, capability, resources,
finances, and social factors, such as air pollution
requirements. Effective system planning considers
the potential place of each alternative in subsequent
programs.
The system planner seeks programs which can
achieve the lowest construction and operating costs
possible within the planning constraints of the
utility or group of utilities for which he plans. In
our judgment these constraints should include severe
criteria for reliability of design and operation applicable to a broad planning region as well as to the
subareas within the regional interconnection.
Reliable service on any system depends on the
careful planning and operation of that system; today’s system planner, however, must be concerned
not only with his own system’s needs but also with
the needs of surrounding systems serving communities hundreds of miles away. Planning and operating
a system successfully, therefore, are exciting processes which require the cooperation of many
individuals.
Key Elements in Reliability
The likelihood of power failures, whether of
major or minor proportions, depends upon the
quality of planning, operation, and maintenance of
interconnected power systems. A weak link in the
chain of producing and delivering bulk electric
power which may cause only a liited interruption
in one instance, can in others, be the precipitating
factor in a widespread failure.
41
Power interruptions may be caused by inadequate
transmission systems, faulty settings or action of
relays, failures in power system equipment, poor
workmanship or maintenance, insufficient provisions
for load relief, insufficient training of operators,
neglect of emergency procedures, communication
failures, defective or inadequate instrumentation,
lack of standby emergency power, willful damage,
severe storms and floods, and many similar factors.
The precipitating causes are numerous, but systems
can be designed and operated to withstand such incidents without an ensuing power failure.
Key challenges confronting reliability of bulk
power supply can be grouped under the following
elements :
(a) Carefully prepared projections of load requirements sufficiently far in advance to permit orderly planning, construction and testing of new
facilities to serve the projected loads.
(b) A transmission network designed to withstand possible disturbances of major proportions.
(c) A frequently reviewed and updated system
of operating controls and protective devices.
(d) Rigorous adherence to well planned and
continually updated operating practices, including provision of spinning reserves, emergency load
shedding, and where appropriate, generator dropping.
(e) Continuous power, isolated from the effects
of a system disturbance, for communications, data
collection, and switching operations.
(f) Standby power for the safe rundown of generating units if system power is lost.
(g) Standby power for rapid restarting of generating facilities.
(h) Use of equipment specially designed to
withstand adverse environmental conditions in
areas where they occur frequently.
This chapter examines in detail these aspects of
power system planning and operation and recommends various means of enhancing the reliability of
interconnected networks.
a
1980 in order that a general pattern of long-range
trends could be identified and analyzed. In the up
dating of the National Power Survey now in progress, the Commission, with the assistance of the in- I
dustry, is extending these projections to the year
1990. Such projections of load and resources permit
a useful generalization of the nature, magnitude and
location of facilities likely to be needed in the fairly
distant future, and hence provide perspective on
how early expansion may be consistent with future i
needs. Long range planning brings into earlier i
recognition the magnitude of problems which will
arise in siting, water supplies, rights-of-way, air and
water pollution and other environmental effects,
and provides a better grasp of topics needing early
study and research. Projections of ener,7 require- I
ments to 1980, developed in the Commission’s National Power Survey, are illustrated in figure 14. I
Intermediate-range projections, about 10 years
ahead, can guide the more detailed planning of
generation and transmission which in a few yean F
will be moving into the final design stages. Pro- I
grams to meet loads 10 years in the future may re- !
fleet new concepts in size and types of generating
units, higher transmission voltages and other technological advances which could require more than
normal time for examination and coordinated planning. The need for this range of planning is underscored by the fact that coordination among a large
number of utilities has become a principal requirement in achieving reliability, and that such coordi-
ELECTRIC ENERGY REQUIREMENTS*
1960-1980
load Projections
A system planner is concerned with assuring that
the needs of every customer will be met. Therefore,
the planning of any system starts with a projection
of future power requirements. Long range load
projections, generally on a service area basis, have
been used by most utilities for many years. The National Power Survey, published by the Commission
in 19&, included load projections of this type to
42
nation (
plannin!
Cons1
facilitie!
of need’
conside:
activitic
expansi
and hc:
forms 0
The
made a
several
the nai
mands
Peaks
contim
day. T
utilitie
Year* I
preced
7.2 pe
trends
which
demo1
develc
the r:
equip,
Ma
areas
ment
ObViO
expec
i n dc
the sz
[ &efc
i apro
lead
mall
undo
l
1970
1960
Includas Industrial InPlant Generation
tLlIi1
from 1964 Nahnal Power SurW
EfoURE
1980
Plan
ing
Arm
14
and
pattern of long-range
analyzed. In the upSurvey now in prog: assistance of the inejections to the year
and resources permit
jlture, magnitude and
e needed in the fairly
Dvide perspective on
:onsistent with future
brings into earlier
problems which will
rights-of-way, air and
nvironmental effects,
! topics needing early
1s of energy requirene Commission’s Na:rated in figure 14.
.ons, about 10 years
detailed planning of
which in a few years
I design stages. Pron the future may re1 types of generating
ages and other techd require more than
nd coordinated plan>f planning is under.ation among a large
I a principal requirend that such coordi-
PUIREMENTS”
nation can add several years to the normal system
planning process.
Construction programs for major generating
facilities must be firmed up, or nearly so, on forecasts
of needs six years in advance. Specific trends to be
considered are near-term commercial and industrial
activities of the area, seasonal trends in population,
expansion in use of electricity for air conditioning
and heating, and the activities of promoting other
forms of energy.
The marked influence of weather on loads was
made abundantly clear in the summer of 1966 when
several utilities in the central and southern parts of
the nation had difficulty in meeting peak load demands during a prolonged period of hot weather.
Peaks were much higher than normal and loads
continued at high levels for many hours of the
day. The peak load of one of the major midwestern
utilities was 12.4 percent higher than the previous
year. Peak loads of this utility had increased for the
preceding five years at an average annual rate of
7.2 percent. Other utilities in the area had similar
trends. This experience emphasizes the problems
which can arise from unexpected load trends and
demonstrates how rapidly a serious situation can
develop from causes such as extreme weather and
the rapid rate of installation of climate control
equipment.
Many instances of power shortages in various
areas of the Nation point to a need for improvement in load forecasting techniques. Although it is
obvious that completely accurate results cannot be
expected, some systems have expended much effort
in developing better methods of forecasting. At
the same time, many reports indicate that too often
the forecasting procedure consists of little more than
a projection of past load growth.
lead Time for Planning and Construction
1980
The elapsed time between the decision to buy
and install an item of equipment and the date
when it is available for service is commonly referred to as lead time. Current reevaluation of
lead time is extending the period beyond that normally allowed in past years. More time is needed
under today’s requirements for broader coordinated
planning. Longer times are elapsing between ordering and commercial operation of new facilities.
Among the causes of frequent delays in manufacturing and construction, are shortages in skilled labor
and Iabor-management disputes, and more exten-
sive testing of new equipment of expanded size and
voltage. Additional time also is needed to obtain
approval from local bodies or federal authorities
of the location of generating plants and transmission lines, and to acquire sites and right-of-way.
A few years ago, utilities generally found four years
to be adequate for the design and construction of
most generating capacity. Lead time for fossil fuel
units now ranges from four and a half to five and
a half years, and about a year longer for nuclear
additions.
Lead time for transmission additions has ranged
from one and a half to two and a half years depending upon line length, right-of-way problems and
terrain, and type of construction. More recently, it
has increased to two to three years and to as high
as four and one half years for some EHV additions.
Considering these trends, firm plans for new facilities
should be formulated as far as six years in advance
of the date of required initial operation. This, however, should not preclude shorter lead time for final
planning and construction of component elements
of system expansion if shorter periods for these elements will not endanger meeting firm schedules
for commercial operation. Indiscriminate use of
expanded lead time could result in adding unnecessarily to the expense of system development or in
precluding use of the latest technological improvements.
System Generating Reserve
In order to provide a continuity of supply, all
power systems must have available more generating
capacity than their aggregate loads. The desirable
amount of this spare capacity, known as “reserve,”
varies from system to system. It is affected by a
number of factors, including system size, the sizes
and types of generating units, system load characteristics, and system maintenance practices. Reserves are needed to offset errors in load forecasting, to replace machines taken out of service for
regular maintenance or emergency repairs, and to
provide minute by minute ready reserve capacity.
Satisfactory operating performance requires the
continuous availability of reserve generating capacity for quick response when unusual demands are
placed upon the system. This is generally called
“ready reserve” and is defined as capacity that can
be produced or supplied in 10 minutes or less.28
g Appendix I, Volume II.
43
Ready reserve for most systems is the sum of two
components : (a) spinning reserve, which is generating capacity connected to the bus and ready to take
load automatically by prime mover control action;
and (b) non-spinning reserve, which is capacity
that can be fully realized within 10 minutes. It may
include quick-starting capacity at rest, such as hydroelectric or gas turbine and diesel engine driven
units ; temporary emergency capacity that may be
obtained from some units by temporarily increasing
steam pressures above normal operating limits, and
at some sacrifice in’thermal efficiency, by.reducing
the amount of steam normally diverted from the
turbine for boiler feedwater heating; loads which
may be dropped under interruptible power contracts; or pumping loads which can be interrupted
quickly at pumped-storage hydroelectric projects.
Typically, a utility or a group of utilities may
maintain a minimum ready reserve of 6 percent of
the area’s predicted load and a spinning reserve not
less than 3 percent of the load. Coordination among
systems with different seasonal load characteristics
can permit substantial reductions in aggregate reserve margins required and at the same time afford
increased system reliability.
Experience during the Northeast power failure
indicated some need to distribute spinning reserve
margins in smaller increments among a larger number of generating units in order to assure faster response. The Regional Advisory Committees’ surveys
of the practices followed by most utilities throughout the U.S., indicate that there is general recognition of the need to maintain adequately distributed
spinning reserves. Providing the desirable amount of
reserve is a problem which requires continual attention because loads rise sharply at peak periods, and
can change rapidly with shifts in the weather and
from unusual local circumstances. Most forms of
spinning reserve, however, are incapable of replacing a major loss in generation suddenly imposed by
the formation of an electrical island, such as occurred in the Northeast failure. This inability is
discussed in chapter 2.
Importance of Transmission in Reliability
The importance of adequate transmission is
clearly expressed in the report of the Commission’s
Advisory Committee on the Reliability of Electric
Bulk Power Supply.
Transmission must be recognized as the principal medium for achieving reliability, both within a system and
through coordination among systems. It is the cohesive
44
force which ties together power systems. Cascading power
failures are usually the result of insufficient capability
within the transmission links of a system or group of sys.
terns to withstand the sudden demands placed upon them
by reason of disturbances arising within or outside the
system. In the interconnected networks, transmission has
the multiple functions of energy transportation and system
integration. The latter involves the need, not only to dis.
patch generation economically, but also to handle emergency flows resulting from facility outages and system
disturbances which will create sudden power swings. Thir
requires maintaining at all times margins of transmission
capability above scheduled transmission line flows so as to
tolerate such power swings. (Emphasis added.)
Because of the self-interlocking character of alter=
nating current, any change in load or generation at
any particular point on an interconnected network
instantly affects the flow of power over connecting
transmission lines. The effect diminishes with increased distance from the point of change as an increasing number of lines and generating units share
in the reaction to it. Such immediately responsive
changes in flow over the transmission system are the
only sources of emergency power available instantaneously to a distressed area.
Weak interconnections which join adjacent re- 1
gions are of little value in improving reliability and,
in fact, can be harmful. The appearance of strength
by the mere presence of connecting links can be
seriously misleading. New and existing interconnections should be examined critically to determine
whether the system has adequate capacity to remain
in operation under a wide variety of assumed serious
emergencies.
The ability of a strongly interconnected network
to withstand a severe disturbance was clearly demonstrated on TVA’s system on January 19, 1964,
when 1,250 megawatts, the full output of TVA’s
Paradise Generating Station was abruptly lost. The
loss occurred when sheet metal from a nearby building was carried by violent winds into the station’s
switchyard, creating a short circuit on the 161-kilovolt bus. Upon loss of the Paradise Station, the frequency on TVA’s system dropped from 60.005 to
59.95 cycles per second. Concurrently, power flows
on TVA’s ties with other systems changed from a
net outflow of 82 megawatts to a net inflow to TVA
of 1,107 megawatts. All spinning generators on the
TVA system responded quickly to the sudden deficiency in generation and within 4f/l minutes overcame the loss. The net outflow returned to 18 megawatts and frequency returned to 60.00 cycles.
During the 4% minute recovery period, TVA increased its generation by 1,240 megawatts. Of this
amount, 300 mc
units and 940 IT
Because TVA’S
strength to car-r
from other syst
and the accom
load and gener
The change i
nections with ot
after the loss of
ure 15. This fig
reserve respond
to normal.
A similar inc
the Virginia E
TWO 500 kilovc
Storm Plant ii
megawatts of gc
tie lines to neig
maining netwc
redistributed M
customer servic
A more det:
transmission in
ity is included
strengthened t
is illustrated a:
gest the appro,
to provide adec
Regional ar
Limiting the
and operation
of immediate
problems of o
but, as mentio
the risk that
regions will be
connections at
opening ties a
disturbance. 1;
entire regional
inability to ret
regions. Inter]
exchange of
prominent exz
and winter sl
nessee Valley 1
tric Companie
Western Miss;
area.
ascading power
ient capability
r group of systed upon them
or outside the
a-smission has
ion and system
rot only to dis1 handle emeres and system
:r swings. Thic
?f transmission
1 flows so as to
d.)
tcter of alter;eneration at
:ted network
‘r connecting
hes with innge as an ing units share
ly responsive
stem are the
lable instanadjacent reliability and,
e of strength
inks can be
interconnec3 determine
ty to remain
tmed serious
ted network
:learly demy 19, 1964,
t of TVA’s
tly lost. The
earby buildhe station’s
he 161-kiloion, the fren 60.005 to
mower flows
ged from a
ow to TVA
rtors on the
sudden de!nutes overto 18 megacycles.
d, TVA intts. Of this
amount, 300 megawatts were supplied from steam
units and 940 megawatts from hydroelectric plants.
Because TVA’s interconnections were of adequate
strength to carry the instantaneous inflow of power
from other systems, isolation of the TVA system
and the accompanying hazard of further loss of
load and generation were avoided.
The change in power flows on TVA’s interconnections with other utilities, immediately before and
after the loss of the Paradise plant, is shown in figure 15. This figure illustrates how TVA’s spinning
reserve responded and restored system generation
to normal.
A similar incident occurred in January, 1967 on
the Virginia Electric & Power Company’s s;stem.
Two 500 kilovolt circuit breakers failed at its Mt.
Storm Plant in West Virginia, tripping off 950
megawatts of generation. Although two 500-kilovolt
tie lines to neighboring s stems were opened, the remaining network ties held and power flows were
redistributed without causing any interruptions to
customer service.
A more detailed discussion of how dependable
transmission interconnections contribute to reliability is included in chapter 6. A general pattern of
strengthened transmission throughout the Nation
is illustrated and described in the chapter to suggest the approximate scope of the additions needed
to provide adequate reliability by 1975.
Regional and Interregional Coordination
Limiting the size of areas of coordinated planning
and operation has some merit from the viewpoint
of immediate economic gains and the practical
problems of organizing and conducting business,
but, as mentioned above, such limitation increases
the risk that interconnections between areas or
regions will be inadequate. Weaknesses in the interconnections at the boundaries may contribute to
opening ties and isolating systems during a major
disturbance. In consequence, the reliability of the
entire regional supply may be seriously impaired by
inability to receive support from systems in adjacent
regions. Interregional connections also permit the
exchange of diversity loads between regions. A
prominent example is the interchange of summer
and winter surplus capacities between the Tennessee Valley Authority and the South Central Electric Companies, a group of utilities operating in the
Western Mississippi-Oklahoma-Arkansas-Louisiana
area.
Progress in coordination has been accelerated
within the last few years, and it is likely that the
size of coordination areas will undergo continual expansion as loads increase, as larger scale generation
and transmission become practical, as utility mergers and other consolidations continue, and as new
techniques and control systems are perfected for
accomplishing satisfactory coordinated operation in
larger areas. Considering the current status of industry development, the physical and electrical
geography of the interconnected network, the practical problems of organization, and the necessity for
inter-area coordination, it appears that the most
practical and effective overall program would be
founded upon close coordination of utility systems
on i. regional basis. The formation of planning
groups directed towards these objectives have been
described in chapter 4.
Network Stability Analyses
Analyzing the stability of large networks under
possible abnormal conditions is an essential part of
transmission system planning. The Northeast failure has spurred the industry to reexamine network
stability utilizing more severe impacts and including
larger areas of the network in the analyses.
The report of the Commission’s Advisory Committee on Reliability of Electric Bulk Power SupPlY 2s recommends the following abnormal conditions as criteria for examining the stability of networks :
The outage of any power plant, including the largest
of any of the interconnected systems . . .,
The outage of the most critical transmission line . . .,
The outage of all transmission circuits on any one common right-of-way . . .,
The outage of an entire transmission substation of any
one of the interconnected systems . . ., and
The sudden dropping of a large load or a large load
center.
Digital computers and sophisticated computer
programs now make practicable the study of large
interconnections, and permit extensive analyses that
were impossible only a few years ago.3o As discussed in Chapter 2, studies of this nature were made
for the Commission by task groups under the supervision of the Commission’s Advisory Panel for the
Northeast Power Interruption.31 Similar studies
Is Included as Volume II of this report.
Jo Appendix G of the Report on the Reliability of Electric Bulk Power Supply.
*I See Volume III.
45
constituted a significant part of the Northeast Tnterconnection Study by a private consultant for the
Northeast Power Coordinating Council.3’
The Report of the Reliability Committee includes
a detailed discussion of various aspects of network
design and operation for system stability and emphasizes the need for capabilities such as high-speed
tripping of circuit breakers to remove as rapidly as
possible the damaging dynamic effects of short circuits, strong network connections to enable emergency power flows without serious overloads, and
high-speed reclosing of breakers to restore system
connections quickly in appropriate situations. The
needs for automatic voltage and frequency regulating equipment in relltion to stable system operation
are also discussed in Volumes II and III.
Appendix A of this report includes a section
devoted to the reports of the six Regional Advisory
Committees on their surveys of recent studies of
network stability under severe disturbances. Many
of the interconnected groups have made comprehensive transient stability analyses using criteria
similar to those recommended by the Reliability
Committee. Other groups have not fully agreed
upon criteria as severe as the recommendations suggest. Still others have not participated in analyses
of severe disturbances on a region-wide basis or
determined the expected performance of their own
systems during disturbances originating elsewhere in
the network with which they are interconnected.
Making broad scale computer studies to investigate network stability and to identify improvements
required to assure reliable network performance
should be an important responsibility of regional
coordinating groups.
Direct Current Interconnections
Direct current transmission has certain characterstics which, for particular applications, may offer
advantages over the usual alternating current transmission. Some of these characteristics are of interest
in considering possible ways of improving the stability of interconnected networks.
Recent advances in dc terminal conversion equipment and reductions in cost have enhanced interest
in and the opportunities for using direct current in
EHV transmission. In the movement of bulk power
for distances up to about 600 miles, ac is more
* Northeast Interconnection Study, Stone & Webster
Engineering Corporation, November, 1966. Summary
recommendations are included in Volume III.
economical; for longer distances dc transmission ?
can have a cost advantage. The dc interties under
construction on the west coast will move power 800
miles between the Pacific Northwest and the Pacific
Southwest.
Direct current transmission has been used in
other countries for the transmission of power by
underwater cables. Because of the problems involved
in transmission of power by underwater or underground high-voltage alternating current cables,33
the cost of ac and dc transmission in such situations
equalizes in the range of 35 to 65 miles.
Direct current provides a means for transmitting
a constant flow of power without regard to many
1 0 hi
225 I
current network such as deviations in frequency,
phase angle or sudden surges of power between the
areas interconnected. In other words, the dc transmission line does not transmit “synchronous power,”
and because of this difference some planners have
considered that direct current interlinks between
major areas could. help to resolve some of the stability problems which have resulted in severe power
interruptions.
As previously stated, ac interconnections have the
characteristic of automatically moving power into -!
areas which suddenly become deficient in power i
supply. A dc line, on the other hand, does not have I
the characteristic of automatic response and cannot resourcefully increase interarea support. Thus,
while dc links could protect against the entrance
I
of undesirable surges from one area to another, they :
are likewise incapable of transferring a desirable
t
surge in power. It is not inconceivable that control 1
equipment could be superimposed upon normal dc
flow control equipment to detect a disturbance and Ii
change the flow of power instantIy to help mainI
:
the complications, cost, and maintenance of such I
equipment are imponderable factors at present.
Thus some of the uniquely desirable characteristics
of ac systems should not be overlooked when comc
paring the two approaches.
as None of the presently known insulating materials suitable for buried or submerged cables are perfect insulators.
Because of this, small currents are produced in the insulation when ac voltages are impressed. These currents pro.
duce losses which heat the cable and limit its load carrying
ability. This problem does not occur with dc systems, and
the absence of the cable charging current and insulation
wear make the dc cable cheaper and practical for distances
beyond the capability of ac cable.
L
ELEC
conditions which normally affect flows in alternating
tain the stability of the interconnected network, but
RE!
Tc
MIDDI
124 MW
TV
RESPONSE OF INTERCONNECTED, NETWORK POWER FLOW
TO SUDDEN OUTAGE OF TVA PARADISE STEAM PLANT
transmission
terties under
e power 800
nd the Pacific
b
January 19, 1964
been used in
of power by
ilems involved
lter or underrent cables,33
uch situations
,m
1 KENTUCKY UTILITIES
r transmitting
Rard to many
in alternating
in frequency,
I between the
the dc transmous power,”
Aanners have
inks between
ne of the stasevere power
Sons have the
g power into
:nt in power
goes not have
nse and canIpport. Thus,
the entrance
another, they
; a desirable
: that control
)n normal dc
turbance and
I help mainnetwork, but
ante of such
1 at present.
haracteristics
j when com-
materials suitfeet insulators.
I in the insula: currents pro.
s load carrying
!c systems, and
and insulation
11 for distances
PLANT /
I
CAROLINA POWER AND
LIGHT COMPANY
18 MW FROM TVA (a)
LEGEND
a - Power flow immediately
before loss of Paradise
b - Power flow immediotely
after loss of Paradise
TVA SYSTEM FREQUENCY SWING
DURING DISTURBANCE
60.1
r1
TVA SYSTEM GENERATION RECOVERY
1
8500
4
4% MINUTES
H
z
ti 60.0
5
-LOSS OF PARADISE
59.8 I
’
I
I
10 PM
I
I
I
-
_
I
I
or'
9 PM
OTHER TVA SYSTEM GCNERATION
"
9:39
"
9:40
"
9:41
,
1
"
9:42
9:43PM
FIWRE 15
47
supply. A deficie
tards the frequer
on the generatin
for an increase il
ning reserve of t
If the network
a disturbance ar
formance. Such
when the large e
areas became is
connected netwc
most immediate
for four minute
The decline in
13.000
showing general arrangement of equipment at north terminal of Pacific Northwest-Southwest direct
current intertie. Buildings house converter valves to change power from ac to dc and vice versa.
FIGURE 16.-Model
These considerations, however, do not diminish
the potential value of dc lines for the movement of
large blocks of power over long distances or for
transferring a block of power betwen power areas
not otherwise interconnected and which could not
be connected by ac lines of comparable cost without
the risk of major instabilities.
Problems of Separated Systems
Regardless of the care with which individual and
interconnected systems are planned and operated,
some extreme event may occur which will cause a
separation of interconnections. It is likely that
should an area become isolated, it will be faced with
a sudden imbalance between generation and load
and may be forced to operate below normal frequency. Under these circumstances, generation and
load balance must be restored promptly if the system
is to continue in operation. Ordinarily, a surplus of
generation is less difficult to a’djust, although the
system frequency will increase momentarily until
the turbo-generator controls react to reduce the output of the machines. Excess generation does carry
the hazard of a generating unit being tripped by
action of overspeed relays, or of an unstable condition developing through the machine’s pulling out
of step.
Instantaneous generator dropping may be helpful
and even essential under special circumstances such
as the sudden loss of transmission lines which are
heavily loaded by the generating source. The objective is to prevent a surge from overloading other I
interconnected lines, causing them to become unstable and trip out.
I
An area which becomes isolated with a substantial deficiency in generation has a serious problem
in sustaining operation and regaining normal power
12.000
z
ZE
9.000
8 000
5
z
s
z
3
2
s
+
7.000
6.000
n
z
ti !
VJ
E
3.000
;
!f
y
u
’
z
5
2.000
g
5.000
4.000
1.000 0
apply. A deficiency in generation automatically relrds the frequency of the power system, and controls
n the generating machines will automatically call
)r an increase in output, bringing into use the spining reserve of the area.
If the network is too weak to remain intact during
disturbance and a system or group of systems be3mes isolated, the reserves may not be able to funcon effectively in accordance with expected permnance. Such was the case of November 9, 1965,
,hen the large eastern New York and New England
reas became isolated from the rest of the interonnected network within seconds after the disturbnce at Niagara. Due to the deficiency in generation,
le frequency of the disconnected area dropped allost immediately to 59 cycles per second, progresvely declined to and remained at about 54 cycles
)r four minutes and finally dropped to 49 cycles.
‘he decline in both frequency and generation is
raphically portrayed in figure 1’7.
Satisfactory operation of steam-electric generating
nits, which made up a large proportion of the
spinning reserve in the CANUSE area, is dependent
upon many auxiliary devices such as boiler feed
water pumps, forced and induced draft fans, and
pulverizing mills for coal-fired units. A reduction in
system frequency reduces the capability of these
auxiliaries and can seriously reduce the capability of
the boiler-generator unit. Unless these auxiliary systems are specially designed to produce rated outputs
at reduced frequency, and few auxiliary systems are,
steam generating units not only may be unable to
increase their output if system frequency has declined to about 58 cycles per second, but may even
have difficulty in maintaining the output which was
being produced immediately prior to the disturbance. Furthermore, operation at such a low frequency for even a few minutes can seriously damage
the turbine blading of large modern units.
The performance of generating units in the
eastern New York-New England area has been
critically analyzed by the special task group appointed by the Commission. Their investigations
are summarized in Volume III.
GENERATION AND FREQUENCY VARIATIONS
Eastern New York and New England
515 to 528 PM November 9, 1965
15.000
\ AREA REQUIREMENT AT
60 CYCLES PER SECOND
14.000
13.000
wthwest direcf
L.
12.000
, 11,000
although the
entarily unti
:duce the outm does carry
lg tripped by
rstable condi‘s pulling out
60
10.000
I
9.000
8 000
7.000
6.000
5.000
lay be helpful
nstances such
es which are
e. The objecoading other
become unh a substanious problem
lormal power
I TIME OF INITIAL
II - D I SDISTURBANCE
TURBANCE
4.000
3.000
2.000
1.000
0
5:15 5:16
5:17
5:18
5:19
5:20
5:21
5122
TIME
5123
5123
5124
5124
5125
5125 5126
5126 5127
5127 5~28
FIOURE 1 7
49
load Shedding
When a system or group of systems has become
isolated and is operating at a marked subnormal
frequency, action should be taken promptly to reduce the load temporarily, so that operation may
be restored to normal frequency. Taking such measures will permit machines with spinning reserve to
increase their outputs more rapidly because power
to their auxiliaries will be less impaired. This also
will permit early reconnection with surrounding
systems and restoration of loads temporarily
dropped.
The frequency at which load reduction begins
varies among systems and among sections of the
country. Different levels may be selected to suit the
ability of the generating plants of a system or group
of systems to operate safely and to respond quickly
under subnormal frequency conditions. The density
and character of the service area may also influence
the program for load reduction. Many systems will
begin load reduction when frequency has fallen
somewhere within the range of 59.5 to 59.0 cycles
per second. The Stone and Webster Engineering
Corporation’s report of the Northeast interconnection recommends that load reduction begin within
the range of 59.7 to 59.3 cycles per second. Successive increments of load shedding should be
scheduled to obtain adequate relief if a serious deficiency in generation occurs. It is suggested that
an adequate program of load shedding should provide for as much as 50 percent reduction in the
load.
It is important that load be shed rapidly enough
to prevent a frequency reduction below about
58.0-58.5 cycles. Otherwise, system recovery, unless
it has large hydroelectric resources, is likely to be
unduly prolonged, inviting further decline and
possible collapse of system power.
Load reduction can also be obtained by reducing
system voltage but reduction by this means is
usually limited to a few percent of total system load.
Small amounts of load reduction may result from
undervoltage tripping of motor loads in industrial
plants if abnormally low voltages accompany a system disturbance. It is a common practice to protect
large electric motors with under-voltage relays.
There are some situations in which planned load
shedding by undervoltage relays is useful or necessary in addition to underfrequency control. The
transmission network in the Pacific Northwest, for
example, has experienced severe under-voltage con50,
ditions upon loss of a main circuit requiring tem- L
porary load relief locally in the affected area. But
the severity of a disturbance is more likely to be I
evidenced by system frequency deviation than by
voltage variations.
Load shedding may not be effective, and in fact
can be hazardous, if not coordinated by systems
which are closely interconnected and likely to continue operating together during an area separation.
:?;
A change in frequency follows area isolation almost
‘i
instantly. Unless arrangements are provided for
rapid automatic control, there is little likelihood of
I
satisfactory load reductions by systems that may be
operating together in the isolated area. As a consequence, an operator who is first to employ load
shedding procedures might find his system carrying !
the brunt of the load relief. Conceivably this could
compound the problem of stability by overloading
ties and causing secondary separation in the isolated
i
area. These factors favor placing load reduction
under coordinated automatic control.
Each system, area and region should carefully I
study its load shedding program to avoid the possibility of overloading inadequate internal ties if the
deficiency in supply is concentrated in a very small !
part of the separated area. Such contingencies may
require special consideration in the application of
automatic underfrequency relays until adequate 1
transmission can be built.
Some utilities serve industrial loads which can be ’
interrupted without significant injury or inconvenience. Often the contracts under which they are
served have special terms permitting such interruptions and include provision for slightly lower rates.
Efforts should be made to avoid shedding loads
identified as highly essential or critical. Some
changes in circuits may be needed to accomplish I
this.
The present application of load shedding on sys-.
terns throughout the United States is illustrated in I
figure 18. Although load shedding is shown to be
utilized in large areas of the Nation, it should not be
assumed that present practices are coordinated ’
fully adequate to meet the needs in all parts of th
areas during severe system disturbances.
Public acceptance of load shedding as a second
ary safeguard against devastating failures can be
expected once its assuring role is understood. Although much can be done to design cascade-fret H
systems, there still can be no ultimate guarantee of
infallibility of bulk power supply, even if utiliti
a
provided virtually complete duplication of powe
buit requiring temb affected area. But
is more likely to be
:y deviation than by
,ffective, and in fact
rdinated by systems
d and likely to con; an area separation.
uea isolation almost
s are provided for
is little likelihood of
systems that may be
d area. As a conseht to employ load
his system carrying
nceivably this could
ility by overloading
,ation in the isolated
:ing load reduction
control.
3n should carefully
1 to avoid the possi: internal ties if the
ated in a very small
1 contingencies may
the application of
lys until adequate
loads which can be
: injury or inconlder which they are
:ting such interrupilightly lower rates.
id shedding loads
or critical. Some
ded to accomplish
Id shedding on sys.tes is illustrated in
ng is shown to be
on, it should not be
tre coordinated or
in all parts of these
%bances.
:ddjng as a secondng failures can be
is understood. Aldesign cascade-free
imate guarantee of
ly, even if utilities
plication of power
UNDER 20%
SCHEDULED FUA lNSTRLlATlUN IN 1967-68
I
~~~)lil’~i’iO OVER 20%
ml
Note: Wide variations occur within shaded blocks in the setting of under frequency relays.
FIGURE 18
system equipment at the enormous cost which this
would entail. The causes which can trigger severe
disturbances are practically unlimited. Many of
them are derivatives of severe storms, seemingly unaccountable equipment failures, or even the fallibility of well-trained system operators and maintenance
men. The customer of a well planned and operated
system should understand that any interruption of
his load through load shedding would be infrequent
and of short duration. The customer should recognize that it is much better to accept a brief load
interruption than to undergo a prolonged disruption in service associated with total system collapse.
Careful planning of load shedding programs and
explaining their purpose to customers and to the
public are important utility responsibilities. Utilities should work closely with state commissions and
other appropriate governmental authorities in setting up their programs of load shedding, and in
establishing suitable procedures for informing the
2867-781
O-67--5
public or parties who may be affected. These measures, properly accomplished, should be helpful in
protecting utilities from individuals who press
claims for damage because of actions for the public good.
Relay and Control Systems
Modern power systems are controlled by a wide
variety of instruments and devices, many of which
function automatically. The art of instrumentation
and control undergoes continual improvement.
Relays are used to protect power equipment and
maintain service. They initiate corrective actions
under abnormal conditions. Most of these devices
are preset for certain limiting power characteristics
and function automatically when these hmits are
reached. Relays can be accurate and dependable in
performance but they require regular maintenance
and inspection. An important need is to update the
million kilowatts, approximately the power requiretional changes k
ment of Washington, D.C. and its surrounding
absolute necessit
suburbs, probably would utilize several thousand
up communicatic
relays on its bulk power supply system. In addition
ppwer supplies c
to those which detect transmission system power
characteristics, others perform functions such as
Computer AF
detecting the formation of gas in high voltage transAnalog and d
formers and sounding an alarm, or removing a geneconomic
dispat
erator from service if excessive temperatures deconnected
netw
velop in bearings or windings.
and
continuous1
Increased dependability and broader control
crements of genl
functions have been the objective of manufacturers
taking into act
and utility engineers in the design of control syscosts, and gene
tems. Many of the relays are actually small comsend signals to
puters which are capable of analyzing a number
automatic incre:
of power system characteristics and taking approinstallations are
priate actions instantly.
they work with
Following the Northeast power failure, many
situation which
power systems across the Nation made special rethe computer. S
examinations of their relay settings and the status of
dispatch do no1
existing equipment. As an example, the Central
era1
seconds or
Hudson Gas and Electric Company reported that 1
tions,
can be dl
all transmission line relay settings were reviewed
computer.
and all protective devices field tested at least once
Without que
between November 9, 1965 and February 1, 1966. c
L utilizing digital
Dependable Communications
FIGURE lg.-Static relay terminal ready for installation.
Solid state devices are replacing many electromechanical components in modern relay design. Typically, the
relays in this terminal might control several hundred miles of EHV line for phase and ground-fault
protection.
setting of relays or install updated relay controls as
the system is modified or expanded to serve increasing requirements. Despite general reliability of relays, improper installation, faulty settings, inadequate maintenance or other forms of deficient operation continue to cause a substantial number of
system interruptions. Six of the 173 significant interruptions in bulk power supply since 1954 resulted
from undesired relay and control circuit performances. The causes include equipment failure, inadequate adjustments, and deficient maintenance.
Closer coordination between planning, operating
and maintenance staffs of utilities will help to eliminate errors in relay settings and better assure timely
resetting or replacement of relays as system conditions change.
Large numbers of relays are required for the
average system. A utility serving a peak load of three
52
The Report on Reliability of Bulk Power Supply 34 points out the complete dependence of system
control and dispatching upon both data and voice
transmission, and emphasizes the necessity of maintaining vital communication links during system disturbances and operating emergencies. To accomplish this, continuously available standby or
auxiliary power supplies must be provided at all
communication, relay, and terminal points.
The report recommends the use of alternative
routes and back-up facilities for all critical needs.
Furthermore, it suggests the various types of communication facilities that are suitable for particular
services and the kinds of standby power arrangements that can supply essential needs during interruptions of the normal sources.
Failure of communications greatly complicated
matters on many of the Northeastern utility systems
during and after the November 9 power failure.
Subsequent actions by some systems have improved
emergency communication resources, and addi*‘Included as Volume II of this report. The detailed
discussion of communications is included in Appendix I
of that report.
1
F IGURE 20.-C<
proximately the power require‘, D.C. and its surrounding
b uld utilize several thousand
&r supply system. In addition
Et transmission system power
1 perform functions such as
P of gas in high voltage transi an alarm, or removing a genif excessive temperatures deindings.
ility and broader control
e
$ objective of manufacturers
[in the design of control sys:lays are actually small combable of analyzing a number
Iacteristics and taking approY.
rtheast power failure, many
the Nation made special rerelay settings and the status of
4s an example, the Central
ctric Company reported that
relay settings were reviewed
ices field tested at least once
1965 and February 1, 1966.
tional changes have been planned by others. The
absolute necessity of providing the necessary backup communication channels and reliable emergency
ppwer supplies cannot be overemphasized.
Computer Application in Con.trol
Analog and digital computers are utilized for the
economic dispatch of power on a number of interconnected networks. ’ These devices automatically
and continuously determine the most economic increments of generation from the numerous sources,
taking into account transmission line losses, fuel
costs, and generator incremental efficiencies, and
send signals to the selected generator to cause an
automatic increase or decrease in unit output. Such
installations are termed “on line” computers since
they work with data describing the current system
situation which is continually supplied directly to
the computer. Since the actions needed for economic
dispatch do not require split-second response, several seconds or even longer periods for some functions, can be devoted to the analyses made by the
computer.
Without question, new functions and controls
utilizing digital analysis will be continuously intro-
duced into the operation of power systems. Continual improvement is being made in display and
print-out arrangements to aid system operators during abnormal conditions.
In addition to display of information, computers
can provide valuable assistance in making a wide
variety of “security” checks on the capability of
transmission networks to handle normal and emergency loads. “Security”, as used here relates to the
assurance that various parts of a system will not be
expected to function beyond their safe load-carrying limits. Security checks are particularly useful
in scheduling operations when equipment is forced
out of service or needs to be removed from service
for inspection and repair or for the connection of
new facilities. The computer can be programmed to
provide reliable answers quickly for both plarined
and emergency situations.
Extensive computer installations are planned or
are being studied by several interconnected groups.
For example, the PJM interconnection will have a
system in service by the fall of 1967 which will continuously maintain economic dispatch of the generators in service, monitor network loading, and check
system security.
Cunications
liability of Bulk Power Supreplete dependence of system
kg upon both data and voice
hasizes the necessity of main!ation links during system dispg emergencies. To accomtsly available standby or
kes must be provided at all
pnd terminal points.
bends the use of alternative
F ilities for all critical needs.
s the various types of comF t are suitable for particular
1 of standby power arrangeiessential needs during interburces.
@ions greatly complicated
j Northeastern utility systems
!November 9 power failure.
pome systems have improved
btion resources, and addi,I1 of this report. The detailed
ions is included in Appendix I
FIWRE 20.-Consolidated Edison Company’s new energy control center in New York City was placed in service in
March 1962.
Perhaps the most imaginative analyses of possible
applications of computers in system control are those
being sponsored by the State of New York and by
the Bonneville Power Administration. The practicability of extensive control systems capable of intelligence reporting and responding to rapidly changing conditions during system disturbances will be
investigated.
The use of computers for power system control
has increased rapidly within the last few years.
About 20 percent of the nation’s electric utilities
now use them for various control functions. Virtually all utilities utilize computers for engineering
design and system planning studies.
The computer installations vary from relatively
small machines which collect data and monitor
operational variables in generating plants and control centers to very extensive and elaborate systems
which analyze interconnected network situations
and transmit control signals to cause automatic adjustments needed to preserve programmed operatinghitsorconditions.
The operation of power systems may continue to
becmne mox~ automatic with further advances in
computesz, sensing devices and communications
systema As higher degrees of automation are accomplished, the operator’s function will change toward
monitoring computer control actions. This pqRSion towad automation, however, will be gradual
and many intermediate developments must come
firsr. &Xajjr advances must come in mariy areas such
assezGqgde&es, rapid and mliile transmission
of da#a to centd wntr01 points, almost instantaneoars onrnpaskr “.“agsis of the da@ coordination
aB ceniza.l and satilite computers, and immediate
&. - - of -czmarol %igd% to actuating devices.
~~as@emhasnotbeenprvposedinpractical
form which could anaiyze and prevent tie splitsecond instability which characterized tie initial
phase of the Northeast Power failure. Even, if
saz&a& e&&o&c equipment were %~va.ilabh, prepamtim a& ,up&ting of the raqvired computer
programs would be a tremendous undertaking.
Furthermore, the very large number of sensing,
oommu&ca&on and analytical devices involved
would be subgct to 4justment, maintenance and
toed t&&dive operation. To provide for wnA ava&abiiy3 two computers would need to
be provided. These are some of the problems that
mnst be taken ‘Il;llto account in evaluating the net
ypir3s af p~uzgmkdy ezxpadd oornputer control.
Restoration of System Sewices
I
Because of the ever present possibility that power
interruptions may occur, it is important that emergency sources of power be provided for the auxiliary
equipment that must continue to function for safe
shutdown of generating equipment without damage, and for its subsequent rapid return to service. I
From an operating viewpoint, it is desirable to I
return steam units to service as quickly as possible
after a shutdown, because the longer they are down, 1
the longer it takes to get them started again. Time !
required to pick up load is closely related to loss
of heat in the boilers, and cooling of the turbine and
generator. This was dramatically illustrated during
the November 1965 power failure. The first units in
the Consolidated Edison system were back in service
in approximately two hours where auxiliary power
was available. Where plants were without auxiliary
power for five or six hours, it took almost that much
additional time to get them ready to carry load
I
again.
Electric generators used in the utility industry are
driven by various prime movers, including hydraulic
turbines, steam turbines, gas turbines, and internal
combustion engines. Each has different startup I
requirements.
Hydroelectric projects, including pumped storage
plants, can be started more quickly than steam units
with their complex arrangements of auxiliary equip- I
ment. Where available, hydro units may offer a
convenient source of emergency startup power for I
steam turbogenerators. Many systems, however,
have no hydro units.
Internal combustion units, such as the diesel engine and gas turbine, usually can be started quickly,
and are self-contained. Gas turbines are being supplied in increasingly larger sizes, with some multiple
unit plants as large as 14O,OOO kilowatts. The time
required to bring a large gas turbine from cold start
I
to full load is about four or five minutes. Therefore,
these units serve well to supply a source of startup or
other standby power.
Many items of auxiliary equipment are necessary
for startup, continued operation, and safe shutdown
of steam-electric generating units. Principal auxil- I
iaries include boiler feed pumps, circulating water
pumps, condensate pumps, draft fans, fuel handling I
equipment, pumps for bearing lubrication and
hydrogen sealing, and turning gears for off-line slow
rotation of turbo-generators. Rotation is needed to t
distribute the residual heat evenly around the tur
bine to pre
which migh
tion during
pumps mus
bearings an
generators.
These au
munication
SOme auxili
ures and SC
Individu
needs that
which are .
for emerge
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emergency
pumps req
ground piI
Lack of
a relative11
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great atte:
Regional i
systems art
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types of pi
November
of the COI
east Powe
sary to prc
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distributes
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hydro rest
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The m
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the Corn
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failed. 7
...on
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lossibility that power
nportant that emerded for the auxiliary
to function for safe
ment without damlid return to service.
nt, it is desirable to
s quickly as possible
mger they are down,
started again. Time
osely related to loss
rg of the turbine and
Iy illustrated during
.re. The first units in
were back in service
Lere auxiliary power
re without auxiliary
>k almost that much
eady to carry load
e utility industry are
including hydraulic
rbines, and internal
s different startup
ling pumped storage
kly than steam units
s of auxiliary equip; units may offer a
y startup power for
systems, however,
ch as the diesel en1 be started quickly,
lines are being supwith some multiple
kilowatts. The time
bine from cold start
minutes. Therefore,
source of startup or
)ment are necessary
, and safe shutdown
Its. Principal auxils, circulating water
fans, fuel handling
g lubrication and
lsus for off -line slow
ltation is needed to
dy around the tur-
bine to prevent differences in thermal expansion
which might warp the shaft and cause severe vibration during later operation. For safe shutdown, all
pumps must continue to function to lubricate the
bearings and maintain the seals for hydrogen cooled
generators.
These auxiliaries, as well as station lighting, communication, and control systems must be supplied by
some auxiliary source of supply during power failures and subsequent restarting of unZs.
Individual systems have specific emergency power
needs that may be peculiar to these systems but
which are just as important as others in providing
for emergency situations. For example, the Commonwealth Edison Company has provided small
emergency generators to supply the cooling oil
pumps required for circulation of oil in the underground pipe-type cable system in Chicago.
Lack of adequate emergency power was noted as
a relatively common deficiency at the time of the
Northeast failure. It is an area that has received
great attention subsequently. The reports of the
Regional Advisory Committees indicate that most
systems are providing sources of emergency station
service power sufficient to alleviate the more serious
types of problems encountered during and after the
November 9 failure. As indicated in the critique
of the Commission’s Advisory Panel on the Northeast Power Interruption, it is not considered necessary to provide “emergency crank-up power sources
at every major generating plant. Appropriately
distributed installations may be sufficient, particularly if systems have ready access to other generating
plants with such crank-up power equipment or to
hydro resources, or if they have provided for separation of generating units from the system so that
generators can be kept operative on their own
auxiliary loads.”
Maintenance
The maintenance of equipment and replacement
of components when improved designs become
available are particularly important factors in reliability. In a large number of failures reported to
the Commission, the initial trouble has been aggravated by the subsequent failure or malfunction
of related protective equipment. Simultaneously,
for example, with the loss of power at Mt. Storm
from breaker failures as described earlier in this
chapter, a dc-powered emergency oil pump also
failed. This resulted in damage to bearings and
seals on one of the 570 megawatt generating units
during the emergency shutdowns, and required returning thespindles to the manufacturer for repair.
Adequate maintenance is a prime factor in
reliability for all power system equipment from the
largest generator to the smallest control device, and
maintenance programs should be directed toward
preventive rather than corrective actions. This
entails firm schedules for overhaul and testing, and
extends into coordinated planning and operation so
that maintenance outages will not reduce area reserves to the point of endangering reliable system
performance. The power interruptions reported in
chapter 3 include a number of failures which resulted from incomplete coordination between staff
elements. It is obvious that not only those involved
directly in maintenance activities, but system operating and design groups as well, should participate in developing maintenance arrangements and
programs. Much emphasis needs to be placed on a
rigorous upgrading of maintenance practices.
Criteria and Standards for Reliability
Investigations since the November 9 power failure
point to the need for criteria and standards as basic
guidelines for improving the reliability of electric
bulk power supply. Although it is recognized that
particular circumstances might sometimes require
consideration beyond a given set of minimum standards, such criteria and standards would help to
eliminate weaknesses which exist in some areas of
planning, operating and maintaining interconnected system facilities.
Planning criteria, for example, could well begin
with load projections and include consideration of
the effects of weather extremes, surveys of appliance
saturation, analysis of load diversity and delineation of areas for coincident peak determinations.
General criteria for stability investigations have
been recommended by the Advisory Committee on
the Reliability of Electric Bulk Power Supply.
Tliere may be reasons, in special circumstances for
increasing or possibly decreasing the severity of
the recommended contingencies. Other elements in
guidelines for stability investigations could include
the appropriate size of the area for analysis, the type
of analytical programg to be employed, criteria for
interregional stability studies, bases’ for describing
system electrical characteristics, and procedures for
establishing and updating regional inventories of
electrical characteristics of facilities for use in
stability studies.
55
Coordinated system planning and design should
consider the matter of centralized area control with
a view towards providing a limited number of
central control offices to replace a large number of
independent control points that currently exist in
some coordination groups.
Design criteria should insure adequate protection
and provide for emergency operation of essential
equipment, power to operate communication networks in the event of system disturbances, and
minimum equipment and facilities needed in control centers to automatically and manually control
interconnected systems. Criteria and standards
should cover emergency power for generating plants
and should consider the underfrequency performance of station auxiliaries.
Because of the dynamic growth in electric loads
and the continual evolution in new equipment and
methods, criteria and standards must remain flexible. Furthermore, conditions vary widely throughout the nation, and what is desirable in one place
may be essential in another, and perhaps even
unneeded in still another.
Operation Guides
For several years the North American Power
Systems Interconnection Committee (NAPSIC) ,
a voluntary organization of representatives of the
operating sector of electric utilities, has issued operation guides to promote uniform and acceptable
practices in interconnected system operation. Some
of the guides pertain to such matters as time correction, and accounting for inadvertent interchange
power flows, but others bear directly upon the reliability of system performance.
Following the Northeast power failure, NAPSIC
undertook a complete revision of its guides and
after extensive deliberation approved an updated
and expanded version for interim use.
Those participating in NAPSIC are among the
best qualified representatives of the operating sector
of the industry and deserve much credit for their
initiative in creating the organization and in
promptly reviewing and improving the guides when
the need became apparent. Of necessity the guides
are a composite of industry thinking and sometimes
a compromise of varying views. However, the committee is serving a useful and necessary function in
56
the discussion and resolution of problems in coordinating operating practices of interconnected
systems.
Need for a Central Study Group
It would be useful for the industry to increase
its coordination in the field of investigation and
analysis to accelerate solutions to challenging problems and attainment of goals in electric system
planning and operation. Many professional societies
and associations have an interest in activities of the
electric utility industry. Some have programs of
continuing data collection and analysis on many
subjects. These activities are praise-worthy and, produce beneficial results, but are characteristically
limited in progress and breadth due to overworked
volunteer assistance or sponsorship by a single industry segment.
It is believed the industry would benefit from
having a central organization supported by all segments of the industry to undertake studies of special
subjects from which much could be gained by concentrating a common exploratory effort. Topics for
coordinated analysis can be drawn from many problem areas in which better solutions would be useful
to the entire industry.
The study of advanced cooling methods; irnproved methods of load projection; nationwide
study of load diversity; analysis of inter-regional exchanges to meet seasonal peaks; assembly and
analysis of data on the performance of generating
units under normal and abnormal conditions; studies of line reclosing problems; recommendations of
advanced methods of security checks of system operation; evaluations of programs for operator training, studies of relative usefulness of various displays
for system operators for prompt appraisal of system
conditions, automatic equipment to analyze system
disturbances and indicate correct emergency procedures-these are a few of the challenges to the
industry today which are worthy of industry’s best
talent.
Investigative activities are generally oriented toward potential economic gains of individual manufacturers or the objectives of special groups. A Central Study Group could, in part, address itself to
explorations left unapproached because of uncertain economic returns.
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1
CHAPTER 6
THE ROLE OF TRANSMISSION IN RELIABILITY
Interruptions in bulk power supply have varied in
size from the unprecedented interruption in the
Northeast to localized incidents such as those resulting from severe storms or the failure of any of the
hundreds of items of equipment in a bulk supply
system. Widespread cascading failures cause the
greatest economic damage and hazard to the public
safety, but any interruption in bulk power supply
is cause for concern. To safeguard the national
interest and the public welfare, the electric power
industry must accept the task of preventing widespread power failures and of reducing the magnitude, frequency, and duration of any bulk power
interruptions to the lowest practical levels.
With the exception of interruptions caused by
unusually severe weather, earthquakes, or other
catastrophic phenomena for which only partial
protection can be provided, the industry has
adequate technical competence, equipment, and
operating knowledge to provide a reliable supply of
electric power. The major defense against power
interruptions, whether large or small, lies in high
quality planning of interconnected power systems
and in strict adherence to carefully developed and
coordinated operating and maintaining programs.
Transmission Objectives
There are three principal objectives in providing
adequate transmission capacity :
1. To support immediately any load area suddenly faced with a serious and unexpected
deficiency in its normal generation supply. The
network must have capacity to handle, well
within stable limits, the automatic inflow of
supporting power, from the hundreds of generators in the surrounding interconnected
network.
2. To transfer, without serious restriction,
capacity and energy within regions and between regions to meet power shortages. Emergencies can arise from innumerable causes,
such as delays in commercial operation of new
generation, problems with new equipment, the
failure of major generating units or other elements of the system, and unexpected peak
demands caused by weather extremes.
3. To exchange power and energy on a regional
and interregional scale, and to achieve important reductions in generating capacity investments and in the cost of energy production.
The value of having a network adequate to meet
contingencies included under objective 2. above is
illustrated by situations in two separate areas of the
nation which are expected to have only marginal
sufficiency to meet the 1967 summer loads.
In the Pennsylvania-New Jersey-Maryland (PJM)
pooling area, the completion of two large generators
has been delayed from the scheduled date for commercial operation earlier in 1967. As a result, generating reserves are expected to fall to the very low
margin of 3!4 percent. Commitments for firm power
from neighboring utilities and load relief through
voltage reduction, curtailment of load in the system’s commercial and office buildings, and curtailment of station light and power at all of the
generating stations will increase the margin to about
8ys percent of estimated remaining load. Additional
power may be available from other utilities as far
removed as Michigan, Ontario, Canada, and New
England in the north, Ohio on the west, and the
Carolinas to the south. Some transmission lines will
be heavily loaded during periods when power is
imported and, in fact, additional power could be
supplied if line capacities were larger. Interconnections between PJM and surrounding utilities will
be substantially strengthened by EHV ties soon
to be placed in service. At present, the capability of
interconnecting lines to surrounding utilities is about
1300 megawatts, less than 7 percent of the area’s
current peak load.
Utilities in the area which includes Minnesota,
Wisconsin, Iowa, Illinois, and part of Missouri,
have experienced faster growth in summer loads for
57
the last two years than anticipated, and will have
a deficiency in normal system reserves in the summer of 1967. Some power will be imported from
surrounding utilities in Indiana and Kentucky. Additional power could be made available from these
utilities and from the Missouri Basin System if
intermediate networks were stronger. It appears
that the margin of generating capability in this area,
normally scheduled to be not less than 12 to 14
percent of the projected summer peak load, will
probably be less than 10 percent this summer.
Bases for Appraisal of Transmission Needs
In order to gauge the general magnitude of desirable network strengthening, the staff of the Commission has made an appraisal of EHV lines that
may be needed by 1975. The stafI appraisal utilized
loads projected for 1980 under the concept that
transmission network capability should lead, rather
than risk lagging behind, the power generation
requirements.
In considering network contingencies, it was assumed that the Northeast disturbance was far from
being the upper limit of impacts that could occur
in the future as loads double and triple. Generating capacity at a single site in the next decade is
likely to reach 3000 mw and the loads carried on
some individual transmission rights-of-way may
reach similar levels. Accordingly, instantaneous
emergency support in large amounts should be
available to areas of concentrated power use.
The staff appraisal was guided in part by an examination of required transmission service to a
number of principal load centers throughout the
country to meet loads projected for 1980. The adequacy of transmission was judged on the ability
d the lines to carry normal and emergency loading
without exceeding 50 percent of the aggregate
canying capacity of the lines, with one principal
line out of the service. The assumed emergency
loads var&~I from a minimum of 1250 megawatts
to a maximum of 3OOO megawatts, representing, in
general, abolnt 2,O TV 25 percent of the total peak
load of the load center. Limiting line loading to
50 percent of a line’s capability was intended to
allow for three principal conditions: ( 1) lines in a
oonaplex network will not necessarily share loads in
ptvpodon t o t h e i r n o m i n a l capabiUes; (2)
dynamic loading from a disturbance can be much
laager than steady-state loading; and (3) a large
maxgin should be available for seasonal or other
diversity flows, economy transfers, and emergencies
which may continue for several weeks or months.
In some areas, the appraisal was guided by prospective interregional power exchanges including
emergency power movements.
Possible Pattern of Needed Transmission
A possible pattern of line additions, considered
to be representative of a suitably strengthened EHV
transmission system to meet projected loads for
1975, is shown in figure 21. About half of the added
lines have already been programmed or are under
consideration by various utilities or pools for completion in the late 60’s or early 70’s. A major portion
of these are in the east central, north central, and
far west regions of the United States. Other lines
have been added where interconnections are nonexistent or are of inadequate capacity.
The depicted pattern is the product of appraisal
and judgment rather than detailed analysis, and
individual lines are not to be viewed as specific recommendations. Rather, the pattern is intended to
present a general outline that would encourage systerns to initiate the detailed studies required for
broad coordination with emphasis on reliability, and
to develop a dependable network that could serve
areas now isolated from, or weakly connected with,
the present main network of interconnected systems.
Additions in EHV lines beyond those scheduled
for service in 1967 include 16,000 miles of 345-kilovolt, 21,4OO miles of 500-kilovolt, 5,750 miles of
765-kilovolt and 1,665 miles of +750-kilovolt dk
transmission circuits.
In the general pattern depicted for 1975, the utilities in the northeast and southeast are more strongly
integrated with the central body of utility systems
in the east. The 765-kilovolt line which is shown on
Figure 21 to overlay the 345-kilovolt network now
under development in New England, is suggested to
enable major flows to take place between the heart
of New England and the central eastern section.
It may be considered by some that 765 kilovolts is
an unnecessarily high voltage to meet prospective
requirements in this area. However, overlaying in
single step increases such as 345-kilovolt with 500kilovolt can be uneconomic. The short time before
another step is needed can result in unnecessarily
short life of expensive equipment or added cost for
large inventories of spare equipment to suit a multiplicity of voltages.
Southeastern utilities are shown to be interconnetted with a 5OO-kilovolt loop which joins with the
loop of corre!
begun to span
board from nor
Strong nort
cated, beginnir
of Michigan, 1
Pennsylvania, 2
to utilities sen
Electric Power
voltage networ
which span a s
Virginia. At PI
of 345-kilovob
overlay networ
197 1. America
tions with 21 s
are at 500 kilt
138 kilovolts. !
transferring 4,
kystem, more
Relatively few
interconnecti
exporting or ir
of peak load I
The Hydrotario has ties v
Michigan, and
The present @
system is abou
1973 is projecl
58 percent wil
tions and 42 p
time, the larg
the Lakeview
with a capaci
plants will in’
plant in westc
Pickering Nut
the new cap:
Hydro’s majol
ancing area lc
Following i
terns with tho
in 1970, On
from Windsor
part of a new
The increase
the western en
flows normal1
the 230-kilovo
loop of corresponding voltage that has already
begun to span a major section of the eastern seaboard from north to south.
Strong north-south interconnections are indicated, beginning in the heavy industrial load areas
of Michigan, Illinois, Indiana, Ohio and western
Pennsylvania, and extending through the TVA area
to utilities serving the Gulf states. The Americin
Electric Power system has an extensive extra high
voltage network interconnecting its six subsidiaries
which span a six-state area from Michigan to West
Virginia. At present, the system includes 1800 miles
of 345-kilovolt transmission lines. A 765-kilovolt
overlay network is scheduled for initial operation in
1971. American Electric Power has 53 interconnections with 21 separate utility systems. Two of these
are at 500 kilovolts, ten at 345 kilovolts and 41 at
138 kilovolts. These interconnections are capable of
transferring 4,500,OOO kilowatts into or out of the
‘system, more than half of its present peak load.
Relatively few utilities in the United States have
interconnections or internal networks capable of
exporting or importing as much as 15 to 20 percent
of peak load requirements.
The Hydro-Electric Power Commission of Ontario has ties with United States utilities at Detroit,
Michigan, and at Buffalo and Massena, New York.
The present generating capability of the Ontario
system is about 8,860 megawatts. Its capability in
1973 is projected to be 15,400 megawatts, of which
58 percent will be in thermo-electric generating stations and 42 percent. in hydroelectric plants. At that
time, the largest thermal generating plant will be
the Lakeview steam-electric station near Toronto,
with a capacity of 2,400 megawatts. Other large
plants will include the 2,000-megawatt Lambton
plant in western Ontario and the 2,000-megawatt
Pickering Nuclear Plant near Toronto. In general,
the new capacity will be located near Ontario
Hydro’s major load centers and should aid in balancing area load and generation.
Following interconnection of the Michigan systems with those to the south in Indiana and Ohio
in 1970, Ontario Hydro’s transmission network
from Windsor (near Detroit) to Niagara will be
part of a new transmission loop around Lake Erie.
The increase in generation on Ontario’s system at
the western end will reduce the magnitude of power
flows normally transmitted from east to west on
the 230-kilovolt network north of the lake. This will
leave more reserve capacity in these lines for handling major disturbances, should they occur at the
major generating centers in Canada or the United
States at either end of Lake Erie. Ontario’s program
includes some additional 230-kilovolt construction s
in this section of its system. Ontario and United
States utilities in Michigan, Indiana and Ohio are
reviewing stability studies to determine whether interconnections now planned have adequate strength
to meet the stability tests suggested in the report of
the Reliability Committee. Design loading of some
of these lines should reflect the likelihood of seasonal power flows between the United States and
Canada. Basically, closure of the loop around Lake
Erie will substantially improve the stability of the
network in this area and increase the reliability of
service to the interconnected load centers in Canada
and the United States.
Interconnections among utilities in the far midwest from the Dakotas and Minnesota in the north,
to Texas in the south, present the problem of economically tying together smaller load centers spaced
farther apart. Here, north-south transmission lines
are generally shown to be 345 kilovolts. Heavier
lines will be needed eventually in the east-west direction to transfer surplus and emergency power,
and to provide some insurance for unforeseen emergencies. The east-west ties are not considered to be
a first priority need but, as stated earlier, are suggested to encourage the systems involved to study
the appropriate configuration for reliable ties between the western and central sections of the continent. An important early step is to complete the
strengthening of the transmission network in the
large western region and the network in the west
central region, particularly in the western section of
the region.
The eastern and western sections of the United
States were successfully joined together for the first
time in February 1967, with the closure of three
230-kilovolt and one 161-kilovolt ties. These lines
are very light for this duty. They cannot dependably move more than a few hundred megawatts in
either direction and therefore, cannot significantly
improve the reliability of the networks of the nation. These ties will separate, as they did on two
occasions in the first two months of closure, when
disturbances occur. These separations have not
caused cascading or loss of customer service. However, the situation needs improvement to relieve
59
c - - - - w - - -
L_/ 1’
\\ /’
’
-d&---\\ \ \
---I\ \ \
‘
\ ./
General Note:
None of the lines indicated on this exhibit is to be considered as a specific
recommendation of the Commission. Further, no recommendation is intended
as to number of lines, levelof voltage, or type of power (ac or dc) for the
principal east-west ties between areas marked with
.>.
1
”
. an asterisk.
FIGURE 21
60
i--------.
! --i----I
1 i
1-‘
i, 1
i
\
\
I
t-
- - - - -
/”
\
\
/’
\’
--/
-\- - - \
\
\
- - 3r-
i
POSSIBLE PATTERN
‘~
\
____
\
\
\
__---
345
KV
___--
500 KV
700+ KV
11-111
POSSIBLE PATTERN OF TRANSMISSION
FOR INCREASED RELIABILITY
BY 1975
61
the utilities in the region from operating under uncertain circumstances. The construction of strong
east-west transmission lines should be of interest to
many utilities in the United States. The merits of
their construction should be carefully studied by
regional coordinating organizations.
The planning and construction of the four major
north-south EHV lines connecting systems in the
Pacific Northwest with those in the Pacific Southwest are progressing, generally on schedule. Part of
the first 500-kilovolt line to California from John
Day Substation on the Columbia River, has been
operating at 230 kilovolts since April 1966. The
operating voltage is expected to be raised to 500
kilovolts by December 1967. The parallel 500-kilovolt line is scheduled for service in May 1968. The
first dc line from the Northwest to .Los Angeles is
scheduled for service in April 1969. A dc line from
the Northwest to the Hoover Dam is planned for
operation in 1972.
The successful operation of these lines will require
a substantial strengthening of the north-south
lines which interconnect in the mountain states to
the east. These lines form the eastern section of a
large transmission loop, of which the new northsouth interties form the western part. Strengthening the eastern portion is essential to prevent frequent separations among utilities in Wyoming,
Idaho, Utah, Colorado and New Mexico. This is
of concern to all of the utilities in the western part
of the United States.. Plans to establish a regional
coordinating organization for the solution of such
problems were announced earlier this year.
Developing a network of the general configuration illustrated in figure 21 by 1975 should enable
utilities to plan with assurance and confidence for
the exchange of power on a regional and interregional scale. Until transmission systems in the
United States are planned and built well in advance of fully demonstrated requirements, the
nation will continue to be faced with the possibility
of further power failures, forced load curtailments,
and the foregoing of economic power exchanges.
Cost of EHV Transmission
Because of differences in design, conductor
materials and sizes, and related elements of transmission line construction, it is difficult to present
a simple comparison of line costs and capabilities.
Nevertheless, the following table shows a general
62
comparison for several EHV levels now in use an
planned for early construction in the United States.
.i
Line Voltage-Kv
230
345
500
750
Range of
Ave39000COBt
Per’Mile
45-60
60-80
S-100
125-160
Approximate Line Capa-
I
10
100 Miles
275
700
1,750
4,4Jm
135
350
850
2,150
The cost of lines depicted in figure 21, excluding I
those in service at the end of 1966, and including
an allowance for new internal lines, substations,
communications, new control centers and other
facilities which would accompany these network
additions, is estimated to be about $8 billion. This I
pattern of transmission, or one of similar strength,
will be needed whether added by 1975 for increased
reliability, or deferred a few years until it becomes
a necessity under less severe reliability criteria. The I
true cost of upgrading reliability to prevent major
failures is the cost of advancing normal transmis- E
sion line construction and appurtenant facilities
over an immediate future period of about eight
years (1968 to 1975). A diagram comparing this
accelerated construction with projected normal
EHV construction, based on recent trends, is shown
in figure 22.
The accumulated incremental expenditures by
1975 for accelerated EHV construction at today’s
costs is roughly $3 billion. This includes the added
EHV lines and associated facilities and, in addition, an allowance of a half-billion dollars for incremental strengthening of lower voltage facilities
to permit full realization of the capabilities of the
advanced EHV system.
It is difficult to depict a long-range projection of
transmission programs which can be correctly classified as an industry projection. The only one currently available was published in Electrical World
I
in 1966, said to have been a nearly complete canvass of the industry. In fairness to industry’s view
of its future transmission requirements, it may very
well be that more transmission lines will be added
as final studies are made of the needs at any point
in time. Whether the difference between the indusi
try projection and the needs suggested in this
chapter is more or less than the $3 billion indicated
1
*Ba
is of no grea
it does not
either to the
nual cost of
$350 milliol
cost of elect
States in 19:
Economic
The bene
are not reac
the health
pairment 0:
nity and h
particularly
considerati
Under a
fits of fully
tan centers
other area
substantial
curred in I
nual cost
may be se1
PROJECTED INVESTMENT IN EHV TRANSMISSION
1 now in use and
re United States.
imate Line Capalility-Mw
1966 - 1975
10-
300 Miles
- ----__
135
350
850
2, 150
.re 21, excluding
i, and including
nes, substations,
rters and other
r these network
$8 billion. This
similar strength,
175 for increased
until it becomes
lity criteria. The
1 prevent major
ormal transmistenant facilities
of about eight
comparing this
ejected normal
trends, is shown
:xpenditures by
ction at today’s
ludes the added
s and, in addiI dollars for involtage facilities
iabilities of the
ge projection of
correctly classi: only one curElectrical World
r complete canindustry’s view
nts, it may very
s will be added
ds at any point
ween the indusgested in this
rillion indicated
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
*Based on a survey by Electrical World, published 10-3-66
FIGURE 22
is of no great significance. Whatever the difference,
it does not appear that it would be burdensome
either to the utilities or to the rate payers. The annual cost of a $3 billion incremental investment is
$350 million, less than 2 percent of the estimated
cost of electric power to be produced in the United
States in 1975.
Economic and Social Justification
The benefits of providing this degree of reliability
are not readily quantifiable. The potential injury to
the health and welfare of persons, the possible impairment of the national defense, and the community and human concern of multitudes of people,
particularly in densely populated areas, are vital
considerations.
Under any standard of measurement, the benefits of fully adequate reliability in major metropolitan centers will far exceed the incremental costs. In
other areas of the nation where density of load is
substantially less and major expense may be incurred in minimizing power failures, the added annual cost of such facilities per unit of power sold
may be several times more than the average for the
country. In such areas, the choice may lie between
acceptance of somewhat higher cost to acquire improved reliability, or acceptance, for an interim
period, of more frequent load shedding to prevent
total failures in power service.
As previously indicated, strengthening the network in the general manner depicted in figure 21
would also open the way for many beneficial exchanges of power and energy among the systems of
the area or region, or between regions. It would
permit the establishment of regional capacity and
energy exchange programs, so that an unexpected
deficiency in any part of the region can be supplied
by the transfer of power from systems located elsewhere in the region, or even beyond the region. Had
a network approaching this strength been in existence in the summer of 1966, the utilities in the central part of the nation which were engaged in the
struggle to maintain electric service during the prolonged heat wave could have been supported by
systems to the north and east which had extra capacity. Similarly, adequate transmission networks
can support utilities or groups of utilities which may
have experienced a serious reduction in reserve
generating capacity because of delays in placing new
63
generating units on the line or because of an abnormally large number of equipment failures. Such
situations are becoming more prevalent as manufacturing and construction delays, and problems in obtaining generating plant sites and transmission
rights-of-way, have seriously delayed the scheduled
on-line dates of new facilities.
The loads in the area including Kansas, Oklahoma, New Mexico, Texas, Arkansas, Louisiana
and parts of Mississippi and Missouri, are an example of the extreme difference between summer
and winter peaks which make interarea and interregional exchanges imperative for economy as well
as reliability. In 1966, the summer peak of the region
was 28,139 megawatts, 16.6 percent higher than in
1965. The winter peak for 1966 was only 18,720
megawatts, although up more than 10 percent from
the previous year. From these figures, it is evident
that the summer peak was about 50 percent greater
than the winter peak which followed. A portion of
this seasonal capacity is being exchanged between
the South Central Electric Companies and TVA,
but a very major part remains surplus. If adequate
transmission is provided, this capacity could be utilized to assist in emergency situations, maintenance
requirements, further seasonal exchanges, and as an
economic supply of energy for future growth in cold
weather loads.
Expansion of the network for reliability in accordance with the general pattern depicted in figure 21
approaches the network strengthening visualized in
the National Power Survey by 1980. It can be expected that the net result of stepping up additions
to transmission systems for reliability would be an
earlier achievement of some of the economic gains
projected in the Survey.
Alternative Considerations for Achieving
Reliability
It may be helpful in understanding the value of
interconnections, to hypothesize on other ways that
utility coordination might have developed. Assume,
for example, that electric systems in the United
States had evolved up to this time in the form of
15-20 operating groups isolated from each other.
Such groups would have individual loads in 1975,
say, of 10-30 million kilowatts each. As a second
alternative these groups could be assumed to be
interconnected with transmission lines of limited capacity, sufficient to take advantage of some seasonal
64
diversity, but not strong enough to remain in service ’ the sudden in
threaten over-k
under severe network disturbances.
With the first alternative, an isolated area with of the loop. Th
an assumed load of 15 million kilowatts, could not I transmission r
which may be
reasonably use units larger than about 700 megai populated, ma
watts. The size of generating plants and the loads
the area. Sucl
supplied through one primary substation or carried
underscore the
on any one corridor of transmission should not exteed about 1000 megawatts. Even so, the sudden I mechanisms tl
loss of 1000 megawatts of generation would result , planning is no
in an immediate drop in system frequency to about
59.5 cycles per second.
I
Under the second alternative with limited capac2
ity interconnections to other systems, the situation
could be less satisfactory. Assume, for example, that
the area had been receiving an inflow of 500 megawatts from neighboring networks at the time of
the loss of 1000 megawatts internally. It is likely that
.
the external ties would become overloaded and trip
Iout. The frequency of the separated area would be
I 111(
expected to drop to about 59 cycles per second. Although a decline in frequency may reduce loads I ,
slightly, a serious disturbance in a network can cause
i
substantial rerouting of flows accompanied by in1
creases in system losses and reactive requirements
;
offsetting the load decreases resulting from lower
1
frequency.
a
Under the alternative conditions described, load
shedding would need to be incorporated into the
planning of systems as an essential working tool to
prevent collapse of power in the area. It would not
be reserved solely as insurance against failure as I
herein for application to strongly inter- -connected systems.
Aside from lesser reliability, these alternative
schemes would be economically handicapped.
Larger generating reserves would be needed to meet F
major equipment failures, unforeseen loads, the ef- 1
:
fects of sharp weather extremes, and the ravages of
severe storms. Diversity power exchanges with other ,
areas would be barred or restricted. In addition,
the limitations imposed on the size of generation t
and transmission equipment would involve increased investment and operating costs.
I
I
Regional and Interregional Planning- and ’
Cost Sharing
Some of the interconnections depicted in figure
21 are of interest and value to utilities outside of 1
the service area in which they are constructed.
Some add strength to large “loop” networks in which
I
I
F IGURE
23.-A
nough to remain in servic
iturbances.
ive, an isolated area wit1
b lion kilowatts, could no
er than about 700 mega
tting plants and the load
mary substation or Carrie1
k;rnisiz; ;zE ;.;te;
If generation ‘would resul
system frequency to abou
the sudden interruption of part of the loop can
threaten overload and instability in the remainder
of the loop. Thus, the cost of required high capacity
transmission necessary for reliability iii an area,
which may be geographically extensive but thinly
populated, may merit the support of utilities outside
the area. Such technical and economic problems
underscore the need for strong regional planning
mechanisms to assure that adequate coordinated
planning is not seriously delayed.
Regulatory agencies as well as utilities may need
to re-examine usual practices of cost-sharing and
cost allocation as interconnecting facilities. are constructed which assure reliability for utilities over a
wide area. Forecasts of needs and values many
years ahead may be required. Exchanges of information and analyses may be required among regulatory
bodies on values assignable to increased reliability
for portions of an interconnected network.
native with limited capac
her systems, the situation
Assume, for example, tha
lg an inflow of 500 mega
networks at the time o
1 internally. It is likely thal
come overloaded and tril
separated area would be
: 59 cycles per second. Al,
luency may reduce load5
Ice in a network can cause
‘lows accompanied by in
reactive requirements
resulting from lower
nnditions described, load
be incorporated into the
‘essential working tool to
in the area. It would not
)rance against failure as
ication to strongly interability, these alternative
nor&ally handicapped.
would be needed to meet
nforeseen loads, the efIitmes, and the ravages of
wer exchanges with other
* restricted. In addition,
n the size of generation
tent would involve in:rating costs.
lional Planning and
ctions depicted in figure
ue to utilities outside of
h they are constructed.
“loop” networks in which
FIGURE
23.-A typical
transmission tower on the Bonneville Power Administration’s segment of one of the 500 kv a~
interties between the Pacific Northwest and the Southwest.
65
CHAPTER 7
OTHER RELIABILITY CONSIDERATIONS
Defense Implications of Power Failures
The Northeast power failure understandably has
created concern that power systems might be more
vulnerable to enemy attack than previously had
been thought. The following paragraphs present
pertinent information about the Northeast failure
as a basis for appraising the probable impact of a
nuclear attack or acts of sabotage on the nation’s
interconnected electric power system.
Defense Impacts of the Power Interruption
The duration of the Northeast power interruption varied from a few minutes in some sections to
as long as 13 hours in parts of New York City. The
impact on the productive capability of the areas affected, however, was not as severe as might be assumed. Since the interruption started at the close
of the normal workday, interference with production was largely confined to those industries working on multiple shifts. Weather was not severe and
there was little damage to production materials or
equipment as a result of climatological conditions.
If the outage had occurred during normal work-day
hours, in a period of severe winter, weather, the
losses in materials, equipment, and production
would undoubtedly have ,been much greater.
Power Systems and Sabotage
The Northeast power failure focused increased
attention on the vulnerability of power systems to
disturbance and damage from acts of sabotage.
For many years the utilities have recognized their
vulnerability to pranksters, vandals, carelessness on
the part of operators, and to unique incidents of
seemingly insignificant origin, such as a bird’s nest
falling on an exposed circuit or the entry of a tree
frog into a relay. Normally these incidents cause
little or no permanent damage and, if service interruption is involved, power can usually be restored
quickly. Automatic protective equipment is usually
successful in confining such interruptions to a
limited area.
Despite past successes, however, it cannot safely
be assumed that electric utilities are adequately prepared to meet the challenge of any concerted efforts
at planned interference. Triggering incidents affecting major supply lines, substations, or switchyards
of large generating plants, could cause protective
equipment to function, or perhaps malfunction, and
result in serious system separations creating imbalances between supplies and loads in isolated areas.
In order to insure against system collapse, existing
networks must be strengthened and a well-planned
program of load reduction must be established. Implemention of this dual program will significantly
strengthen the electric power industry’s ability to
offset any effects of sabotage. Strong and flexible
transmission networks are clearly essential to the
nation’s security in a society so dependent on the
availability of adequate electric energy.
As a check against sabotage-as well as vandalism-many utilities have established security programs. At present, few of these programs are vigorously administered. Most utilities screen and check
new employees during a probationary period prior
to granting them permanent status.
Historically, utilities have taken special protective
measures during wartime periods. During World
War II utilities made more stringent security
checks, and in addition to the normal precautions
of fencing and floodlighting, they closely guarded
critical power system facilities and maintained
vigilant plant entrance restrictions. As power systems become larger and more complex, maintaining adequate security is increasingly difficult. Special precautionary measures should be well planned
in advance, to be instituted in the event the nation’s
security is again directly threatened.
The Provost Marshal General of the United
States Army conducts an annual survey of several
hundred facilities in the United States which supply
electric energy to important defense production
areas. The survey includes reviews of measures for
67
control of entry to critical areas, prevention of sabotage, fire protection, civil defense, minimizing the
effects of damage, restoration preparedness, and continuous staffing by qualified personnel. The capabilities of the utilities are rated as “adequate” or
“inadequate” under both normal and emergency
conditions, the latter including both enemy attack
and civil catastrophe. In the survey for fiscal year
1965, 92 percent of the utilities were rated as being
adequately prepared for normal conditions and 77
percent were considered adequately prepared for
emergency situations. With respect to measures for
controlled entry into critical areas, including prevention of sabotage, 85 percent were found adequate under normal conditions and 56 percent under
emergencies. The survey results underscore the need
for improving preparatory measures to strengthen
electric utility security controls in order to meet any
untoward contingencies which may arise. In addition, it would appear advisable to broaden the scope
of security guidance and coverage to include all
electric utilities by making available to them the
established security criteria developed by the Provost
Marshal General.
Vulnerability of Power Systems to Nuclear Attack
Utilizing patterns of nuclear attack furnished by
defense planning agencies, studies have been made
of the effect a nuclear attack might have on power
systems. These patterns generally have assumed a
large number of surface explosions of major nuclear
weapons at principal population and industrial centers. Based on guidelines of the destructive effects
of these weapons at various distances from the explosion centers, these studies have provided estimates of the effect of postulated attacks on electric
utility operations and electric utility loads in the
affected areas. The studies, which include a nationwide study by the Defense Electric Power Administration and a regional study made by the Triangle
Research Institute for the FPC in connection with
the National Power Survey, led to the general conclusion that the electric power industry’s usable
capacity following attack will exceed the needs of
the surviving loads. This conclusion is based in part
on the overall ability of electric power systems to
overcome the loss of individual electric facilities, and
in part on the long periods following any widespread attack during which industrial and commercial activity would be reduced.
68
Attributes of Power Systems in Surviving
Severe Damage
Severe damage to main generating equipment
would be serious and could require several months
to a year or more for repair. Damage to transmission
and distribution facilities usually is not as serious,
although principal substations, if severely damaged,
could require time consuming repairs. Generally,
however, substation equipment can be repaired or
by-passed much more readily than can complex
generating facilities. The strength of electric power
systems and their ability to cope adequately with
acts of sabotage or widespread attack which temporarily cause system outages, rests with the ability of
each utility in an interconnected system to restore
any essential lines to service and meet any generating deficiencies by obtaining power from alternative sources.
The random destruction from nuclear attack
could cripple an electric system in a manner that
would, in some respects at least, be similar to that
which results from severe storms. The American
Electric Power System, for example, was hard hit
in April 1965, by a tornado that caused loss of
service on seven 345 kilovolts lines and twenty-one
138 kilovolt circuits. The damage, however, did not
bring about a cascading failure within the AEP or
neighboring systems. Automatic protective devices
disconnected the damaged circuits and left alternative ones in service. Largely because of the strength
of the AEP network and its many interconnections
with other systems, service was maintained in the
undamaged areas.
For strongly interconnected systems with adequate arrangements for emergency load shedding,
a nuclear attack will not necessarily touch off cascading power failures. To avoid cascading outages,
however, systems must be prepared to survive ran
dom network separations.
Some consideration has been given to the advisability of planning the temporary separation ol
systems in a predetermined optimum pattern im.
mediately following a warning of impending nuclear
attack. The objective of such separations would bf
to prevent the possibility of cascading power fail
ures triggered by loss of large blocks of capacity a
a result of major damage to transmission lines, sub,
stations or generating plants. The theory that pre,
separation of the network might be beneficial under
broad scale attack is founded on the probabilit!
that damage would be directly inflicted on only i
limited number of the separated network sections
Lnd although p’
damaged sectiol
tions would be u
Defense expel
ably anticipate II
prior to an att;
would need to
periodic practic
terns quickly an
carry out. Many
which is general
transmitted OVE
many cases, sep
require a major
ning reserves, a
For separated
power from sol
dary, it is like1
would be no mc
attack separatio
with random UI
must be overcc
resulting from e
Fallout She1
In the event (
people will be cc
some of the she
plies, no gener
power service h
lit shelters sure
Department of
iary power wet
type of shelter,
and opportuni
manually powe
range of risks i
tend a massive
plies to shelter
in occurence tl
visions for mir
overall conseqi
discomfort ratl
@ The warnins
the country not i
much longer. Tl
arrival of the rad
winds, would ra
most areas of the
Systems in Surviving
‘Damage
ain generating equipment
uld require several months
Lir. Damage to transmissiori
I usually is not as serious,
tions, if severely damaged,
‘uming repairs. Generally,
ment can be repaired or
L dily than can complex
strength of electric power
’ to cope adequately with
zread attack which tempoES, rests with the ability of
jnnected system to restore
vice and meet any generining power from alternaion from nuclear attack
system in a manner that
at least, be similar to that
re storms. The American
‘or example, was hard hit
nado that caused loss of
volts lines and twenty-one
damage, however, did not
failure within the AEP or
:omatic protective devices
d circuits and left alterna:ly because of the strength
its many interconnections
ce was maintained in the
hcted
systems with adeFmergency load shedding,
Inecessarily touch off casL avoid cascading outages,
1 prepared to survive rants been given to the ad! temporary separation of
d optimum pattern imt-‘ng of impending nuclear
mch separations would be
of cascading power failarge blocks of capacity as
to transmission lines, submts. The theory that premight be beneficial under
1 nded on the probability
brectly inflicted on only a
arated network sections,
P
and although power might be lost in the directly
damaged sections, generation in undamaged sections would be unaffected.
Defense experts advise that we cannot reasonably anticipate more than 10 or 15 minutes warning
prior to an attack.35 System separation therefore
would need to be preprogrammed and subject to
periodic practice. The wholesale separation of systems quickly and effectively is difficult to plan and
carry out. Many load areas are supplied with power
which is generated several hundred miles away and
transmitted over an interconnected network. In
many cases, separation into “local systems” would
require a major pickup in generation by local spinning reserves, and preprogrammed load shedding.
For separated sections which normally received
power from sources outside the separation boundary, it is likely that the consequences of attack
would be no more severe than those caused by preattack separation. In short, the problems associated
with random unplanned system separation can and
must be overcome if we are to minimize outages
resulting from enemy attack.
Fallout Shelters and Power Requirements
In the event of a nuclear attack, large numbers of
people will be concentrated in fallout shelters. While
some of the sheIters may have auxiliary power supplies, no general program for providing auxiliary
power service has been instituted for the many public shelters surveyed by the Office of Civil Defense,
Department of the Army. Requjrements for auxiliary power would vary widely, depending upon the
type of shelter, available space, potential occupancy,
and opportunity for natural ventilation or use of
manually powered devices. However, in the whole
range of risks and damaging events that would attend a massive attack, the loss in electric power supplies to shelter areas would likely be more random
in occurence than wholesale. With reasonable provisions for minimum standby power facilities, the
overall consequences would be inconvenience and
discomfort rather than disaster.
“The warning time to detonations, if any, for areas of
the country not included in the initial attack, obviously, is
much longer. The time between the detonations and the
arrival of the radioactive fallout, due to its spread by upper
winds, would range from 30 minutes to many hours in
most areas of the country.
Summary
Electric power systems are subject to damage from
sabotage and from direct enemy attack. The severity of the impact could be as great as that on November 9, but the consequences need not be a massive cascading if power systems are strongly interconnected, and are provided with controls which
will assure immediate balancing of load and generation should the network separate. The availability of strong transmission facilities with a large reserve capacity above normal maximum loading will
be highly beneficial in preventing major power failures and in re-routing power from undamaged generating plants to undamaged and surviving loads.
Such availability would also facilitate the reconstruction or repair of damaged facilities.
Emergency Power for Essential Public
Services
The Northeast incident demonstrated the necessity for emergency sources of electric power to maintain vital services during major failures of normal
power supply. It also pointed up that planning,
maintaining and operating emergency facilities are
di.%cuIt problems for most individual users. A
large number of emergency sources did not function
or functioned inadequately because of poor maintenance, lack of fuel, or absence of qualified operators. Outstanding among facilities which had inadequate auxiliary provisions was the Kennedy
International Airport. This installation had been
considered invulnerable to power interruption because it is supplied by seven principal distribution
feeder lines. All of them, however, received power
from a single utility system, so the entire central
service supply failed during the November 9
emergency.
A large number of these observed deficiencies are
being rectified. A summary of the responsibilities
and activities of various organizations which have
a ihare in planning and maintaining emergency
facilities or in establishing regulations governing
their provision is presented in appendix D. Federal,
state, county and municipal governments are all
concerned. Proposals have been placed before the
Congress which would offer support for the installation of emergency power facilities in some critical
areas.
The dependence upon electric power is critical in
health services. However, since emergency routines
are characteristically a part of hospital services, the
69
power failure was only a temporary inconvenience
to patients and staff at those facilities where emergency generators were available and operative. In
New York City only about half the hospitals had
adequate auxiliary power, and the ratio was even
worse in some other areas. In many instances, local
government agencies and public utilities made available mobile generating units to provide emergency
service. Fortunately no deaths were attributed to
the power failure, but the results might have been
different if the emergency had involved a large influx of injured persons. At best, the necessity of
providing auxiliary power in all hospitals and developing improved procedures for emergency
switching and maintenance were too readily apparent. As a result of this experience, much new equipment has been installed, and emergency facility
codes for hospitals and nursing homes have been
reviewed and strengthened.
Urban transportation dependent upon utility systems for its power supply was seriously affected by
the power outage. In New York City, the power
failure resulted in a complete cessation of subway
operations. As a consequence, auxiliary gas turbine
generators have been installed by the Consolidated
Edison Company for essential lighting and controls,
and to bring subway trains to the nearest station
platform, one at a time, for the discharge of passengers. The cost of an independent generation and
transmission system to provide total emergency subway service is considered to be prohibitive.
The power outage impact on street vehicular
traffic in large metropolitan areas was evidenced
by congestion and traffic snarls that resulted from
the failure of traffic light systems. In a national
emergency involving a need for mass movement of
people out of target or contaminated areas, such
traffic tie-ups might constitute life-or-death hazards
to the persons involved. Recircuitry of a major traffic light system to permit the use of standby power
service, however, is very expensive. As an emergency
expedient, New York City’s Department of Traffic
has expanded and reoriented its mobile unit communication system so that it can now maintain a
reasonable control of sensitive emergency traffic situations.
For the general public in the affected areas, communications interruptions were not intolerable.
Many radio broadcast stations had auxiliary power
sources and were able to maintain service. Batterypowered radios were able to receive broadcasts, and
some television service was maintained for battery70
powered receivers and for standard sets where emergency power was available. This communication
service was undoubtedly a major factor in avoiding
public excitement. All major metropolitan broadcasters have now installed emergency power equipment to insure continuity of service during emergencies.
Telephone services were maintained throughout
the affected area although dial tone and throughconnection delays were experienced in the heavy
trafhc following the power interruption. Prior planning for emergency operations resulted in continued
local, intercity, long distance and even overseas 1
service, and did much to help prevent panic. Commercial telephone systems are equipped with standby battery and auxiliary power generators which
automatically take over if commercial power
falters or fails. In addition, a reserve supply of
portable generators is kept on ,hand as further backup, ready for dispatch to key locations. During the
night of the power failure, 15 Bell System emergency centers were activated, and loans of generators were made to such essential users as hospitals,
convalescent homes, railroad and airline terminals,
and fire and police departments. The telephone
companies in the Northeast helped to coordinate
emergency activity in the public interest by maintaining liaison with government agencies, power
companies and the general public. All Federal systems under GSA control have, since November
1965, been provided with auxiliary power support
to maintain continuous telephone service.
Telegraphic services failed during the blackout
because of lack of power sources in central offices
and at terminal receivers. These weaknesses have
been remedied in the major telegraphic switching
areas and power packs are available for terminal
customers as a tariff item.
Generally, auxiliary power was available for such
essential public services as fire and police protection,
although some central-station operations had to be
curtailed. A problem developed in many public
buildings where power was not available for services
such as elevators and water and sewage pumping.
Some municipal water supply and sewage disposal
functions were weakened, or in some cases failed
entirely, but no serious problems developed as a
result of the difficulties encountered. The potential
for serious sanitation and health problems was
readily apparent, however. Since the power failure,
the building developers have accelerated the practice of equipping high-rise building with auxiliary
power for
ings and p
entities ha
power in t
failures. I
departmel
ditional p:
of auxilia
York City
Centers a
The Cor
proposed
lature th.
Water Su
public ut
A num
tities, nc
emergent
installatic
Electric
planning
ties of inc
the urger
type of si
of the cu
can be of
arrangen
ply with 1
and rem
and open
could va
contract1
nance.
Equipm
The r-c
lated to 1
Equipme
sonable
specified
utilizing
and pro\
nance.
Some :
ment, pi
new 50C
little mo
formers i
breakers
tion of tl
capacito:
!ard sets where emerrhis communication
or factor in avoiding
metropolitan broadrgency power equipervice during emerintained throughout
1 tone and throughenced in the heavy
rruption. Prior planesulted in continued
and even overseas
Irevent panic. Comquipped with stand:r generators which
Commercial power
r reserve supply of
and as further backtcations. During the
Bell System emernd loans of genera11 users as hospitals,
td airline terminals,
nts. The telephone
:lped to coordinate
c interest by mainnt agencies, power
lit. All Federal sys:, since November
iary power support
: service.
uring the blackout
es in central offices
K weaknesses have
legraphic switching
ilable for terminal
available for such
d police protection,
jerations had to be
d in many public
vailable for services
I sewage pumping.
hd sewage disposal
some cases failed
ns developed as a
:red. The potential
rlth problems was
the power failure,
:elerated the praclmg with auxiliary
s
Power for safety lighting, moving elevators to landings and pumping water and sewage. Local political
entities have become aware of the need for auxiliary
power in the event of widespread commercial power
failures. Fire, police, sanitation, and public works
departments have assured service continuity by additional procurement and by improved maintenance
of auxiliary power generating equipment. In New
York City all five Borough Emergency Operating
Centers are equipped with auxiliary power units.
The Corporation Counsel’s Office has submitted
proposed legislation to the New York State Legislature that would give the City’s Department of
Water Supply,,Gas & Electricity direct control over
public utility services in the City of New York.
A number of states, and other government entities, now ,have legislation requiring auxiliary
emergency power in specified buildings and
installations.
Electric utilities generally do not participate in
planning and maintaining emergency power facilities of individual users. While the determination of
the urgency of the need and the magnitude and
type of supply required is largely the responsibility
of the customer, it appears that the serving utilities
can be of important assistance in suggesting suitable
arrangements for coordinating the emergency supply with the utility supply and suggesting procedures
and reminders for periodic maintenance, testing
and operation of the facilities. The responsibility
could vary from one of general advice to formal
contractual service for installation and maintenance.
Equipment Reliability
The reliability of a power system is closely related to the satisfactory operation of its equipment.
Equipment reliability is obtained by specifying reasonable performance margins, testing to verify
specified performance, providing proper operation,
utilizing appropriate control and protective systems,
and providing adequate regular and special maintenance.
Some failures have occurred in major new equipment, particularly in items designed to operate on
new 500-kilovolt transmission systems. Within a
little more than two years, six 500-kilovolt transformers and a larger number of 500-kilovolt circuit
breakers have failed, causing delays in initial operation of these systems. Other devices such as coupling
capacitors and lightning arrestors also have failed,
!2%7-781 O - 6 7 - 6
but with less disturbance to schedules. Improved
performance, however, can be expected. It appears
now that design changes and other modifications
resulting from failure experiences have rectified the
difficulties.
The impact of some of these failures in new
equipment can be serious. Usually there are no
spares for such new equipment and repairs may involve lengthy delays for return of the equipment to
the factory. The number of failures suggests that
present concepts and procedures for proof testing
are not always sufficiently profound to demonstrate
fully the reliability of the equipment under actual
system operating conditions and demands.
An increasingly significant problem in testing
EHV equipment, particularly for short circuit capacity, is the extremely high current requirements.
For some tests, only the large utilities have the necessary current-carrying capacity, and there may be
undue risks in using these systems for short circuit
test purposes.
It appears that the industry would do well to increase its testing facilities to avoid unnecessary delays in the utilization of new devices. While there are
some 20 laboratories for testing high-voltage equipment in Europe and Japan,36 two manufacturing
companies have the only laboratory facilities in the
United States which can be considered reasonably
adequate for testing large circuit breakers and other
system components for maximum duty. Many other
American manufacturers use foreign laboratories.
Generally, United States utilities have not had laboratories for major testing, and many of them have
been cautiously unwilling to use their system facilities for extensive testing operations.
Preliminary plans have been developed for a test
facility near Grand Coulee Dam in the heart of the
major hydroelectric network of the Pacific Northwest. The benefits from such a facility warrant careful consideration by the Federal government, the
utilities, and the manufacturers of major equipment.
It would reduce testing time which is an important
item in the total schedule of new major facilities
and would permit subjecting the equipment to some
as Of the foreign laboratories, 11 are operated by electric
equipment manufacturers and thus are not generally available for use by American manufacturers. The four foreign
laboratories principally used by American manufacturers
are N. V. Tot Kearing van Electrotechnische Materialim
(KEMA) at Arnhem, Holland; Centro Electrotechnico
Spe.rimental Italian0 (CESI) at Milan, Italy; Centre de
Recherches et d’Essais de Fontenay (Fontenay) at Paris;
and Allmanna Sveska Elektriska Aktieholaget (ASEA) in
Sweden.
71
system operating conditions not fully reproduced in
U.S. laboratories.
Reliability also can be enhanced by wide dissemination among utility groups of information about
equipment failures and troubles which would provide a forewarning of possible needs for preventive
action. Information of this type is issued to users of
similar equipment by many of the equipment manufacturers, but much of the reporting may tend to be
limited more to major items of equipment than is
desirable.
Research and Development Needs
Because the advances in electric technology
usually attract little public attention, the public generally does not realize the amount of effort which the
industry devotes to research and development. Traditionally, most of this has been performed by the
equipment suppliers, with the cooperation and often
at the suggestion or urging of the utilities. More
recently the utilities have directly supported R & D
activities, not only on an individual basis, but also
jointly, particularly through the Electric Research
Council and the Edison Electric Institute. However,
with the mpid expansion of the industry, even more
extensive research and development effort will be
required to advance technology, especially in areas
where extrapolation of present designs and practices
is likely to be inadequate to meet future needs.
Following are a few of the many areas which need
further exploration. Significant work is already being done or is planned in most of them.
Further substantial advances in high voltage
technology will be needed .to accompany the continued progression to higher load densities. Plans are
underway to investigate transmission voltages as
high as 1,500 kilovolts. There is evidence at such
voltages, that phenomena not yet well understood
may present new problems, and that significant
changes in insulation materials and systems may be
needed before equipment at the higher EHV levels
will be available for satisfactory operation.
Another area of possible improvement is in
switchgear where high capacity solid state devices
offer some promise of decreased interrupting time,
less complicated arc extinction, higher reliability,
and lower maintenance requirements.
If highly sophisticated applications of computer
controls to systems of automation for electric network supervision and operation are to be achieved,
many improvements must be made. These involve
improved sensing devices, better communication
72
links, means of high-speed analysis and automated
decision techniques.
Nuclear power generation has made rapid advances recently but still further advancement in
the field of breeder type reactors is eagerly awaited
and predicted to be the answer to a continuing
search for lower cost sources of electric power.
Present estimates indicate suitable breeder types are
likely to be commercially available sometime between 1980 and 1985. Extensive research and development is being expended in their development.
There is a need for extra high voltage underground cables and methods of significantly decreasing the costs of underground installation. The Electric Research Council has recognized these needs
and has proposed research and development programs which it is hoped will produce useable solutions to at least the technical problems. Appreciable
decreases in costs seem to be necessary before the
use of underground circuits can be expected to
expand appreciably.
Improvement in reliability of performance is a
worthy goal in all aspects of power system equipment and operation. Every increment in improved
reliability makes possible a reduction in reserve capacity of installed facilities. Reductions of this type
can significantly aid in justifying expenditures for
work which promises improvements in any of these
areas.
Capacity Requirements in Relation to
Manufacturing Capability
An important element in scheduling the planning and construction of new bulk power supply
facilities is the time required for manufacturers to
produce and test heavy equipment ‘such as large
boilers, steam turbines, generators, nuclear reactors,
transformers and related accessories. The rapid
increase in the use of larger size units in the last
six to eight years has permitted the manufacturers
to keep pace with the increasing capacity requirements without having to expand production
space greatly. The larger units weigh less per kilowatt of output and take up less manufacturing
space.
This situation has changed in the last few years
with the sharp increase in the ordering of nuclear
generating plants. Turbines and generators powered
by low pressure steam from nuclear plants are
much larger per unit of output and occupy more
space in the factory than a conventional unit. This
means that as present types of nuclear capacity
become a larg
total kilowatt :
ing plants will 1
In 1965, elc
ordered 24.4
generators, of 1
nuclear-powen
to 18.5 million
million kilowz
United States
orders in corn1
turbine general
illustrated in f
sharp increase
difference betv
of manufactur
large power t
The latter indi
of orders. Trar
influenced by t
These large I
two years, on
what in adva
This is partly
M4
STEAM TI
10
100
1
1962
m The overall
to 4 conventiona
bd analysis and automated
neration has made rapid adstill further advancement in
ype reactors is eagerly awaited
I the answer to a continuing
6t sources of electric power.
tcate suitable breeder types are
cially available sometime be5. Extensive research and detpended in their development.
br extra high voltage under:thods of significantly decreasground installation. The Elecil has recognized these needs
search and development pro)ed will produce useable solu$&al problems. Appreciable
in to be necessary before the
~circuits can be expected to
iability of performance is a
ects of power system equipiivery increment in improved
le a reduction in reserve caP
Ilities. Reductions of this type
in justifying expenditures for
improvements in any of these
become a larger part of total new capacity, the
total kilowatt production capacity of manufacturingplants will be reduced.37
In 1965, electric. systems in the United States
ordered 24.4 million kilowatts of steam turbine
generators, of which 4.9 million or 20 percent were
nuclear-powered. In 1966, nuclear orders jumped
to 18.5 million kilowatts, 41.5 percent of the 44.5
million kilowatts of large capacity ordered by
United States utilities. Tlne large accumulation of
orders in comparison with orders shipped of steam
turbine generator capacity in the years 1962-1966 is
illustrated in figure 24, which clearly depicts the
sharp increase in orders in 1966 and the wide
difference between new orders and the present rate
of manufacturing production. The situation for
large power transformers is shown in figure 25.
The latter indicates only a moderate accumulation
of orders. Transformer production is, of course, not
influenced by the type of generating plant.
These large orders for nuclear capacity in the last
two years, on the whole, have been placed somewhat in advance of normal ordering schedules.
This is partly because more time is required from
MANUFACTURE OF
STEAM TURBINE GENERATORS
10,000 Kw and larger
IOO-
bments in Relation to
pability
I
lent in scheduling the plann of new bulk power supply
kquired for manufacturers to
ivy equipment such as large
, generators, nuclear reactors,
L ted accessories. The rapid
[ larger size units in the last
ipermitted the manufacturers
’ increasing capacity requireg to expand production
b
ger units weigh less per kilo,take up less manufacturing
banged in the last few years
se in the ordering of nuclear
bines and generators powered
m
I from nuclear plants are
iof output and occupy more
n a conventional unit. This
types of nuclear capacity
I
80 -
/
O N O R D E R , ENDY)
60 -
MANUFACTURE OF
POWER TRANSFORMERS
240
r
501 Kva and larger
/
ON ORDER, END OF YEAR
160 -
1963
1964
1965
1966
YEAR
FIGURE
/
/
40
t
1962
1963
1964
YEAR
1965
1966
FIWRB 25
the planning decision to generator startup for
nuclear plants. However, the speed up in ordering
is prompted to some extent by the concern of utilities to obtain a reasonable place on manufacturers’
booming lists of advance orders. As of the first
quarter of 1967, the tivo principal manufacturers
of large steam turbine generators were quoting deliveries in the first and second quarters of 1972.
Allowing a year for installation and testing, this
indicates a lead time of at least six years from order
to commercial operation.
The following illustrates year-to-year increases in
peak loads for the electric utility industry in the
contiguous United States.
1961-62 . . . . . . . . . .
1962-63 . . . . . . . . . .
1963-64 . . . . . . . . . .
1964-65 . . . . . . . . . .
1965-66. . . . . . . . . .
24
m The overall space relationship is about 3 nuclear type
to 4 conventional type turbo-generators of a given output.
/ ,'
,
S H I P P E D DURING YEAR
SummerMillions of kw
(Gidawatts)
2
/
cumulative
Total. . . . . . . . .
8.0
-
10.4
15.5
11.3
17.6
62.8
DecembrxMillions of kw
(Gigawatts)
10.5
5.8%
10. 1
7.0%
9.
8%
9.8
5yC
9.3
6.
13.5
9.5%
........
7.6%
6.7Y0
6. 1%
5.5%
7.5%
53. 2
73
The average annual increase in summer loads for
the last three years in the above table is nearly 15
gigawatts, which closely approximates the indicated
total manufacturing output in 1966.38
Based on information published by Edison Electric Institute in its 41st Semi-Annual Electric Power
Survey, April 1967, the past and projected shipments of turbo-electric generators by United States
manufacturers are as follows :
Megawatts
Outside
U.S.
1966 . . . . . . . . . . . . . . .
1967 . . . . . . . . . . . . . . .
1968. . . . . . . . . . . . . . .
1969 . . . . . . . . . . . . . . .
1970 . . . . . . . . . . . . . . .
12, loo
19,400
22,700
25,400
24,000
Total
-15,500
21,400
24,600
26,400
24.000
3,400
2, ooo
1,900
l,Oc@
..*......,
It is possible that the projected shipment for 1970
may not be inclusive of all orders that will pass
through the manufacturing process in that year.
The principal manufacturers have recently announced plans for expanding production facilities
of steam turbine-generators. The current and projected production capability of these U.S. manufacturers is as follows:
1967
I
i
22,060mw.. . . . . . . .
1970
1971
27,000mw... . . . 28,500mw.
These projections take into account the mix of
normal and conventional type turbo-generators on
order. Based on the foregoing, it appears that
planned expansion of manufacturing plants should
provide a reasonable margin in plant production
capacity for the next five or six years.
Manufacturers need the help of good load forecasting as much as the utilities. Moreover, since they
serve the requirements of the entire nation, longrange comprehensive plans, which are indicative of
the range of Sizes and total capacities of various types
of generating equipment, are of much interest and
o Added annual steam electric generation can be compared approximately to total annual load increases. New
steam elect,ric generation is running about 85 percent of
total new generation in the United States. New steam
electric capacity additions, however, must include about
15 percent for reserve capacity.
value to them. The suggestions for coordinated
regional planning in this report should result in
improved projections and be helpful to manufacturers in the timely planning of adequate production
capacity.
Preservation of Aesthetic Values
Recent events have made aesthetics a primary
concern of management in planning and operating
electric utility systems.
As the population has increased and land use has
become more concentrated, the public has become
increasingly concerned with aesthetics in all phases
of development. It has become an important and
early consideration in power system planning.
The electric utility industry has responded to this
new challenge and is devoting greater attention toward improving the appearance of existing facilities
and to the design and location of new facilities.
Recent trends include the development of new types
of construction materials; blending construction
into the surroundings; increasing the capacity of
existing transmission facilities to avoid the necessity
of acquiring new rights-of-way; utilization of existing rights-of-way for recreational and non-power
uses; and continuing research to discover more economical and practical ways to place transmission
and distribution lines underground.
There are major problems, both technical and
economic, in putting high voltage transmission lines
underground. Underground Power TransmissionA report to the Federal Power Commission by the
Commission’s Advisory Committee on Underground
Transmission, April 1966-discusses the outlook for
new ideas which are considered worthy of research
and investigation, and analyzes the relative cost of
underground versus overhead transmission for a
variety of conditions. The Electric Research Council, formed in 1965 with representation from all
segments of the utility industry, recently adopted a
program of research and investigation in underground transmission which is directed toward the
development of high-voltage underground equip
ment up to 500 kilovolts and the improvement of
installation techniques. It is contemplated that these
efforts will be supported with both non-Federal and
Federal funds. The Secretary of the Interior has requested an appropriation of $2 million as the initial
part of a program to support the Federal interest in
underground transmission research.
Present high-voltage underground construction is
generally from 10 to 20 times more costly than over-
head transmission of
improvements in unc
petted, they may not
wide cost differential
lengths of high-volt
tional problems arise
In the developmen
power system facilith
the public be kept it
and their economic
equally important fc
that the public dem;
high standards of ae:
reliability. If the indl
and provides an ear
its plans, it will ha
reducing delays whit
reliability of bulk po
Technical Talent
The increasing dij
taming adequate pn
of electric utility 01
facturers, and regl
serious problems. ?
to the cause fall into
as:
1. The industry c
sophistication I
for a high or
planning ant
systems.
2. The industry
the space am
programs.
3. Many uoiven
doned program
Universities cl
try do not sup]
gineering as t
ence and other
4. Universities st
the professor
needed and
cooperative 1
fellowships.
A recent survey
sion of 129 colleg
technical curricula
institutions now 0
engineering. But m
suggestions for coordinated
this report should result in
and be helpful to manufacrnning of adequate production
tsthetic Values
made aesthetics a primary
t in planning and operating
F
Ls increased and land use has
rated, the public has become
d with aesthetics in all phases
as become an important and
I power system planning.
industry has responded to this
devoting greater attention topearance of existing facilities
Kd location of new facilities.
the development of new types
‘als * blending construction
asing the capacity of
es to avoid the necessity
* utilization of existnal and non-power
research to discover more ecoll ways to place transmission
1 underground.
problems, both technical and
Ggh voltage transmission lines
ground Power Transmissionral Power Commission by the
y Committee on Underground
966-discusses the outlook for
nsidemd worthy of research
analyzes
the relative cost of
1
‘overhead transmission for a
The Electric Research Counwith representation from all
k industry, recently adopted a
j and investigation in underwhich is directed toward the
Cvoltage underground equip
tolts and the improvement of
. It is contemplated that these
with both non-Federal and
kretary of the Interior has relion of $2 million as the initial
)~pport the Federal interest in
sion research.
underground construction is
L times more costly than over-
head transmission of equivalent capacity. Although
improvements in underground construction are expected, they may not substantially alter the present
wide cost differential. For other than relatively short
lengths of high-voltage cable installations, additional problems arise in operation and maintenance.
In the development of more aesthetically pleasing
power system facilities, it is of great importance that
the public be kept informed of new developments,
and their economic and practical feasibility. It is
equally important for the industry to be mindful
that the public demands considerations of the same
high standards of aesthetics it has come to expect of
reliability. If the industry keeps the public informed,
and provides an early opportunity for comment on
its plans, it will have taken a major step toward
reducing delays which could seriously endanger the
reliability of bulk power supply.
Technical Talent for the Industry
The increasing difficulties of acquiring and maintaining adequate professional and technical staffing
of electric utility organizations, equipment manufacturers, and regulatory agencies are creating
serious problems. The various views advanced as
to the cause fall into several general categories, such
as:
1. The industry does not adequately portray the
sophistication of its needs and the opportunity
for a high order of technical innovation in
planning and operating electrical power
systems.
2. The industry is outbid in securing talent by
the space and other government sponsored
programs.
3. Many universities have curtailed or abandoned programs in power system engineering.
Universities claim that government and industry do not support research in power system engineering as they do in electronics, space science and other scientific pursuits.
4. Universities state that a closer relationship of
the professor and student to the industry is
needed and could be encouraged through
cooperative programs of employment and
fellowships.
A recent survey by the Federal Power Commission of 129 colleges and universities which have
technical curricula revealed that only 29 of these
institutions now offer programs in power system
engineering. But more revealing still is the acknowl-
edgment by many of these schools that their power
system programs have limited attraction to students.
Some courses are available for which no classes
have been formed in several years. Out of the 29
schools, perhaps only 15 can be said to have
reasonably active programs in power system
engineering.
An educator from a large midwestern university
reported that only 25 students are majoring in
power, out of a total enrollment of 500 .junior and
senior students in electrical engineering. He believes
the trend in part has resulted from the availability
of federal funds for research in other lines of electrical engineering and the lack of similar programs
in the electric power field. The students, for example, see great activity in areas related to electronics and information processing, and conclude
that the power-related areas are unimportant. He
believes that support from both private and federal
sources must be made available to foster basic research and development at the universities in power
systems including their control. He further observes
that utilities salaries are not as high at the start as
in other fields, nor has there been any indication
that this is made up by faster advancement later.
Similar observations were received from several
other universities.
There appears to be a relatively rigid attitude on
the part of some employers that specific education
or experience in power system analysis is essential
if the applicant is to be considered. Undoubtedly,
the average employee who has become expert in
power system planning and operation has gained a
large measure of his knowledge and ability through
study and application subsequent to his academic
years. For the aggressive individual, this can be selfinduced; for others it can be acquired through formalized training programs of the employing organization. In any event, in-house programs for
training persons with sound technical foundations
can be of substantial aid in meeting the problems of
personnel shortage.
Although many utilities contract with qualified
consultants or consulting engineering organizations
for parts of their engineering analysis and design,
it is the general practice to perform a large share
of the engineering work within the operating organizations. The expanding demands for comprehensive system and inter-system studies may exceed
the capabilities of utility staffs in several specialized
areas and there may be greater need to call upon
consulting firms for these services. Such use should
75
help to expand the resources of technical talent
available to the industry, and enhance the overall
attractiveness of electric systems as a field of technical endeavor.
The attraction of adequate numbers of qualified
people to the electric utility industry is an important
factor in planning for increased reliability. In this
brief review, it is not intended to ignore the enlightened action of some utilities and organizations
in supporting chairs and fellowships at universities,
in conducting cooperative exchange programs with
universities and colleges and in offering summer
programs for professors and students. But industry
wide, these efforts are modest.
direction of a voluntary organization, UCPTE,S*
composed of representatives of the eight countries.
In addition to UCPTE, which was founded in 1951,
a number of other coordinating organizations have
come into being in various parts of Europe, as
shown in figure 27.
Operations are guided essentially by working
groups of experts who deal with technical problems,
examine economic effects and prepare recommendations, which, however, are not obligatory. Subordinate groups examine questions involving service,
the operation of thermal power stations, and the
operation of hydroelectric projects.‘0
Observations on Power Systems of Other
Countries
UCPTE has recommended to all participants of
the interconnection that sufficient spinning reserve
be maintained to limit frequency variation to onehalf cycle per second, which is equivalent to a spinning reserve of four to five percent. Also, if a frequency decrease cannot be avoided, provisions are
recommended for suitable load shedding. Most of
the interconnected systems maintain protective controls at the borders between countries to open the
circuits in the event that a disturbance occurs on the
interconnected network which could affect the stability of the system within the protected country.
Under a typical arrangement, the country import-
A general review has been made of power systems in a number of other countries with emphasis
on any particular practices in planning and operation which might have useful application in the
United States. Table 5 compares the magnitude of
electric power installations in the United States with
nine other countries having the highest installed
capacity.
International
Interconnections
The largest interconnection of power systems outside of the United States (figure 26) is located in
western Europe and includes eight countri&Belgium, West Germany, France, Italy, Luxembourg,
Netherlands, Austria and Switzerland. Power is exchanged between these countries under specific contracts between two or more parties, but the operation of the network as a whole is under the general
TABLE
Interconnected Operations
19 Union for the Coordination of the Production and the
Transmission of Electricity.
” The information on European interconnections has
been summarized largely from the paper on “Economic
Problems in the Operation of Integrated Power Transmission Systems in Europe,” presented by Franz Hintermayer
at the World Power Conference Sectional Meeting in
Tokyo, 16-20 October, 1966.
5.-Cafiaci& andjmduction of electric systems, U.S. and othr countries-?965~rcliminary da&
I
Installed
Hydro
united states . . . . . . . . . . . . . . . . . . . . . .
U.S.S.R . . . . . . . . . . . . . . . . . . . . . . . . . .
United Kingdom. . . . . . . . . . . . . . . . . .
Japan . . . . . . . . . . . . . . . . . . . . . . . . . . . .
GermBny (west). ..................
Canada. . . . . . . . . . . . . . . . . . . . . . . . . . .
France ..: . . . . . . . . . . . . . . . . . . . . . . . .
Italy . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Germany (East). . . . . . . . . . . . . . . . . . .
swcde.n ...........................
44,490
22,250
1, 760
16,284
4, 064
21,792
12,631
14,272
349
9,297
Capacity-Mw
Thermal
210,030
92,550
46,650
24,815
35,878
7, 602
15,447
10,824
10,311
2,411
I
Total
Production-Million
Hydro
_254,520
114,800
48,410
41,099
39,943
29,394
28,078
25,096
10,660
11,708
196,984
80,617
4,612
75,464
15,145
116,712
46,429
42,831
562
45,966
6
Thermal
Total
_1, 157, 583
480,383
184,266
181,942
160,554
143,161
101,442
80,287
49,958
%fjOO
960,599
399,766
179,648
106,478
145,409
26,449
55,013
37,456
49,396
2,532
7
Kwh
-
-
PRIN
GREAT E
~ta.ry organization, UCPTE,*e
ntatives of the eight countries.
‘E, which was founded in 195 1,
xndinating organizations have
various parts of Europe, as
uided essentially by working
I deal with technical problems,
ects and prepare recommenter, are not obligatory. Subdne questions involving service,
amal power stations, and the
:ctric projects.‘O
,ected Operations
PRINCIPAL TRANSMISSION LINES IN WESTERN EUROPE
1966
GREAT BRITAIN
mended to all participants of
@it sufficient spinning reserve
bt frequency variation to one, which is equivalent to a spinif” five percent. Also, if a freLot be avoided, provisions are
itable load shedding. Most of
items maintain protective conbtween countries to open the
bat a disturbance occurs on the
irk which could affect the statithin the protected country.
ngement, the country importlination of the Production and the
ity.
r European interconnections has
i from the paper on “Economic
on of Integrated Power Transmis’ presented by Franz Hintermayer
lonference Sectional Meeting in
1966.
c preliminary data
Production-Million Kwh
yo
984
617
I,612
,464
, 145
,712
,429
;831
:562
;966
Thermal
960,599
399,766
179,648
106,478
145,409
26,449
55,013
37,456
49,396
2,532
Total
1, 157,583
480,383
184,260
181,942
160,554
143, 161
101,442
80,287
49,958
48,500
LEGEND
- 380K” TRANSMISSION LINES
.....***** 220K” T R A N S M I S S I O N L I N E S
- DC TRANSMISSION LINES
N U M B E R O F CIRCUITS
FIGURE 26
ing power receives a first warning by an alarm signal
if the flow of power on the interconnection reaches,
say, 95 percent of normal maximum value. A second
alarm might be received at 105 percent, and at 135
percent the line would be opened. With this procedure, the importing country may have several
minutes to reduce the amount of power imported by
increasing the output of its generators or by curtailing loads.
Inter-ties are usually protected by underfrequency
relays which may operate either with delayed action to give a few minutes warning or may open the
inter-tie as soon as a specific level of subnormal frequency is reached. Under these provisions, the interconnected network serves well for economic exchanges and has been of assistance in preventing
loss of power on a system of an interconnected member nation. It is not designed, however, to provide
major assistance to member countries experiencing
a severe diiturbance.
EUROPEAN POWER POOLS
27.-European Power Pools
UCPTE-Union for the Coordination of the Production
and the Transmission of Electricity
UFIPTE-France-Iberian Union for the Coordination
and the Transmission of Electricity
SUDELSouth-European Union for the Coordination
and the Transmission of Electricity
NORDEGScandinavian Power Pool
COMECON-Communist Eastern European Power
Pool
FIGURE
78
Many aspects of interconnected system planning
and operation are summarized in a UCPTE article
“Mesures Propres a Eviter des Perturbations Importantes sur les Reseaux d’Intercormexion,” extracted from Bulletin Trimestrial IV 1966. Many of
the practices described are similar to those commonly used in the United States.
Examples of Particular Systems and Practices
The power systems of the major countries of
Europe and of Japan are fairly well interconnected
and controlled. The practices followed, although
varying from one nation to another. are generally
similar to those utilized by interconnected systems
in the United States. Transmission at 225-kilovolts,
275-kilovolts and 400-kilovolts prevails in most 01
the larger countries.
Power installations in France, totalling more than
25,000 megawatts, are about equally divided be
tween thermal and hydroelectric stations. Electricite’
de France, a national organization which produces
about two-thirds of the country’s power supply, has
a central dispatching office in Paris and eight regional centers. The system maintains spinning reserve capacity equal to three to five percent of the
system load or enough to cover the loss of the largest
line. Each area of the system carries an appropriate
part of this reserve to maintain area security. As
much as 70 percent of load can be shed in successive blocks from 48.5 to 47.5 cycles per second (cps) .
The normal frequency of European systems is 50
cps as opposed to the United States standard of 60
cps. This load shedding program has been in use
since 1938, and since 1945, has been a statutory
requirement.
The supply of bulk power in England and Wales
is under the direction of the Central Electricity
Generating Board, a national organization. CEGB
operates eight regional load dispatching offices
under the general direction of the central load dispatching office in London. Systems in Scotland are
under separate control but are interconnected with
the CEGB system. The peak demand for England
and Wales in 1965 was 35,000 megawatts, with aa
installed capability of 36,600 megawatts. Most of
the power is generated in central and northern
England and Wales by coal burning steam-electric
stations, and is transmitted to load centers in central and southern England through a network of
five double circuit 275.kilovolt lines.
Planning of the transmission system is based on
the assumption that system integrity must be main-
tamed with the
transmission lint
Generation is
margin above t
winter. This is
some load in ac
average of one 1
needed, five ste
duction in systf
per second ; sect
with a load red)
each stage ; thir
tor output, limil
capable of augl
700 megawatts :
which are interr
fifth, manual (
shedding in tht
plans are bein
frequency relay
Installed cal
megawatts, of
The Swedish !
tional grid syst
tion. The nets
kilovolt circuit!
hydroelectric !
Sweden to loac
operating trite
the north-soutl
circuit. Transi
network are m
puter program:
On the basi
number of ye
Board has eval
interruptions a
power, plus 4C
eration, the 1~
duction cost. 1
the Swedish S1
to the Northe:
of approximat
to rough estim
east failure.
As mention1
Swedish Boar
north-south tr
viding for the
planned in thf
certain gener
tripped, upon
lterconnected system planning I
arized in a UCPTE article
viter des Perturbations Imc
beaux d’Interconnexion,” exTrimestrial IV 1966. Many of
ed are similar to those com,ted States.
ular Systems and Practices
of the major countries of
are fairly well interconnected
practices fohowed, although
tion to another. are generally
:ed by interconnected systems
Transmission at 225-kilovolts,
l-kilovolts prevails in most of
IS
in France, totalling more than
about equally divided be%roelectric stations. Electricite’
organization which produces
country’s power supply, has
1office in Paris and eight retern maintains spinning re6 three to five percent of the
I to cover the loss of the largest
system carries an appropriate
:o maintain area security. As
Bf load can be shed in succeso 47.5 cycles per second (cps) .
:y of European systems is 50
United States standard of 60
ing program has been in use
e 1945, has been a statutory
power in England and Wales
m of the Central Electricity
Inational organization. CEGB
al load dispatching offices
tion of the central load dis1
don. Systems in Scotland are
bl but are interconnected with
he peak demand for England
‘as 35,000 megawatts, with an
f 36,600 megawatts. Most of
ted in central and northern
coal burning steam-electric
Ritted to load centers in cenlgland through a network of
5.kilovolt lines.
msmission system is based on
ystem integrity must be main-
tained with the loss of a complete double circuit
transmission line.
Generation is planned for a 17 percent capacity
margin above the projected loads for an average
winter. This is said to require the interruption of
some load in addition to voltage reduction on the
average of one winter in twenty-five. If load relief is
needed, five steps have been provided: first, a reduction in system frequency from 50 to 49 cycles
per second; second, voltage reduction in two stages
with a load reduction of about 3 to 31/z percent for
each stage; third, an emergency forcing of generator output, limited to about one hour’s duration and
capable of augmenting the supply by some 600 to
700 megawatts; fourth, disconnecting certain loads
which are interruptible under tariff agreements; and
fifth, manual or automatic load shedding. Load
shedding in the past has been done manually, but
plans are being formulated for utilizing underfrequency relays.
Installed capacity in Sweden is nearly 12,000
megawatts, of which about 9,300 is hydroelectric.
The Swedish State Power Board controls the national grid system and about 45 percent of production. The network consists principally of five 400kilovolt circuits extending 400 to 600 miles between
hydroelectric generating plants in the north of
Sweden to load centers in the south. Planning and
operating criteria require integrity of operation of
the north-south transmission system after loss of one
circuit. Transient and steady-state analyses of the
network are made, using sophisticated digital computer programs.
On the basis of a, comprehensive study made a
number of years ago, the Swedish State Power
Board has evaluated the cost to the nation of service
interruptions at 20 cents per kilowatt of interrupted
power, plus 40 cents per kilowatt-hour of lost generation, the latter being about 50 times the production cost. As a matter of interest, engineers of
the Swedish State Power Board applied their values
to the Northeast interruption and obtained a figure
of approximately $80 million, which is comparable
to rough estimates of the tangible cost of the Northeast failure.
As mentioned earlier, a principal concern of the
Swedish Board is maintaining the integrity of the
north-south transmission system. In addition to providing for the loss of one line, other actions are
planned in the event of an emergency. For example,
certain generators in the north are automatically
tripped, upon loss of lines, to prevent overloading
and instability tripping of other lines. Load shedding is practiced in southern load areas if needed,
but a general program of underfrequency load
shedding has not been adopted. If loss of power
should occur, restoration procedures are based on
rapidly mobilizing the northern hydro resources.
Power Failures
No formal record of power failures in other countries is available, but general information has been
obtained from various sources, much of it through
technical exchange visits of government and industry representatives, who have provided information
on failures which have occurred. The causes are
similar to those which have initiated failures in the
United States. The system planners and operators
in these countries are also concerned with the need
for incorporating any improvements in planning
and operation which will raise the standards of reliability in bulk power supply and, above all, prevent
major cascading failures. The Northeast failure has
alerted electric utility officials in all countries with
well-developed systems to the magnitude of failure
that can occur. The Commission’s December 6,
1965, report on the Northeast power failure has been
translated into a number of languages and widely
reviewed in foreign countries.
A few of the major failures which have occurred
in recent years in other countries are summarized
in the paragraphs following. They illustrate difficulties similar to those experienced in the United
States :
The loss of 3,000 megawatts, about 75 percent of
total system load, of the Kansai Electric Power
Company in Japan on June 22, 1965, as a result of
a landslide which damaged a transmission line. Full
restoration of service was completed within three
hours.
On March 27,1959, the entire Belgian system was
interrupted while carrying a load of 2,200 megawatts. The interruption was precipitated by failure
of a 36,000~volt cable, followed by breakup of the
150-kilovolt network, frequency decay, and loss of
generators because of overload or loss of auxiliaries.
0.n January 24, 1966, a 220-kilovolt breaker exploded near Lyons, France, resulting in the loss of
about 2,000 megawatts of generation for up to an
hour.
A failure caused by transmission line &lays set
at limits that were too low occurred in 1961 in
northeast England, and affected part of London.
One relay operated as its load setting was reached,
79
and other lines opened quickly in sequence, causing a loss of power which lasted from five to six
hours.
Northern Italy experienced a power interruption
on October 13, 1964, when an electrical storm
tripped two lines in central Italy, causing lines which
were importing 1000 megawatts of power from
Switzerland to trip on overload. The northern industrial area became isolated from the main systems of
Italy and southern Europe. Frequency dropped to
48.2 cycles per second for six minutes, then momentarily to 47 cycles when a thermal plant tripped out
on loss of auxiliary power. This was followed by the
loss of about 4000 megawatts of power in the entire area. Service was restored in about 19 minutes.
On January 8, 1966, a defective line connector
caused a 130-kilovolt line to open in the vicinity of
Naples, Italy, causing four other lines bringing
power to the Naples area to trip, interrupting service to the area. Other lines which had sufficient
capacity to carry the extra load temporarily tripped
out because a relay had been set too low. Power was
restored over a period of 20 minutes to nearly five
hours.
The entire system of Switzerland was lost for
about an hour on January 17,1963. This was caused
by an overload and tripping of ties with other
countries. It occurred when attempts were being
made by Switzerland to make up a deficiency of
200 megawatts suddenly lost in an interconnected
country.
On June 12, 1960, the system of West Germany
separated into two parts as the result of the cascade
tripping of north to south ties. The northern part,
along with Denmark, continued to operate but the
southern portion was lost. All service was restored
in two hours.
International Technical Exchanges
Knowledge of new developments and new prcr
cedures is continually exchanged between power
system experts of the United States and those of
other countries. Papers summarizing results of research and studies are presented at meetings of various international organizations such as the World
Power Conference and CIGRE.‘l Equipment manufacturers in many countries have extended their
sales and service programs to all parts of the world,
a Conference Intemationale des Grands Electriques a
Haute Tension.
80
and thus have intimate knowledge of planning and
operating practices of systems in many nations
Visi.ts are frequently made between countries to ob
serve and discuss trends and practices. Many d
these international reviews are supported by gov
emments as well as by power supply entities.
Comparability
In general, power systems in the United State
and in other countries utilize similar equipment and
follow similar practices in planning and operation
Although systems of Western Europe are extensive11
interconnected internationally, only limited reliana
is placed on these ties for emergency support. Be
cause of the absence of political boundaries, inter
connection and coordination in the United State
have advanced further than elsewhere. In spite 0:t
the diverse structure of the U.S. power systems;,
coordination in this country probably will continue !
c
to progress at a faster rate than in other parts of the .
world.
A number of practices of interest have been ob
served in reviewing systems in other countries. Some
systems, notably Electricite’ de France, have pro
vided elaborate display of power flows and system I
conditions on a current basis, giving operators
I
knowledge of conditions that exist at any time. Most
systems utilize or are installing computer systems for
analyzing data, for security checks, and, in a few I
cases, for the economic selection and dispatch of
power. Italy has strengthened its north-south network and has a substantial reserve capacity in its
transmission system for potential impacts. It has
installed a number of frequency relays which are.
actuated by a time-rate of frequency decay, in addition to fixed low frequency tripping. Several of the
European systems require full capability of steam~
plant auxiliaries at frequencies as low as 46 to 48
cycles per second (50 cycles per second is normal) 1
and one system is installing gas turbine generators
to- furnish power for steam-plant auxiliaries at normal frequency if system frequency declines. Atten- I
tion is being directed to arrangements which will
permit quick isolation of generating units in time
of severe system trouble to prevent loss of units if
system power collapses.
In summary, it can be said that the best prz~tice~
in a number of other countries are generally equivalent to the best practices in the United States. NO
new developments were found in the planning and
\
ff
operation of p
a panacea for
or in the Unit
The intensii
tion internally
suming nation
exist in well-cc
The interconn
tte knowledge of planning and
of systems in many nations.
de between countries to obP
ends and practices. Many of
eviews are supported by govy power supply entities.
mparability
systems in the United States
s utilize similar equipment and
xs in planning and operation.
Western Europe are extensively
lationally, only limited reliance
w for emergency support. Beof political boundaries, interdination in the United States
,er than elsewhere. In spite of
t of the U.S. power systems,
~untry probably will continue
: rate than in other parts of the
operation of power systems abroad which represent
a panacea for power failure problems either there
or in the United States.
The intensity of interconnection and coordination internally in a number of the larger power consuming nations is comparable to conditions which
exist in well-coordinated areas in the United States.
The interconnection and coordination among sys-
tems and regions throughout the United States has
developed further, on the average, than among nations in Europe. The scale of power use and service
territory in the United States is larger, and opportunities generally are more abundant and attainable for conserving reserves, for making economy
and diversity exchanges, and for mutual support to
meet emergencies.
‘ces of interest have been o
Iiterns in other countries. Some
ttricite’de France, have prolay of power flows and system
,rrent basis, giving operators
ons that exist at any time. Most
installing computer systems for
k curity checks, and, in a few
mic selection and dispatch of
mgthened its north-south netstantial reserve capacity in its
or potential impacts. It has
frequency relays which are
1k of frequency decay, in addiency tripping. Several of the
uire
full capability of steamP
uencies as low as 46 to 48
cycles per second is normal)
b”
talling gas turbine generators
team-plant auxiliaries at nor1 m frequency declines. Attenb to arrangements which will
m of generating units in time
ible to prevent loss of units if
Es.
1 be said that the best practices
countries are generally equivaitices in the United States. NO
ere found in the planning and
81
CHAPTER 8
THE COMMISSION’S RESPONSIBILITIES AND ACTIVITIES TO IMPROVE
COORDINATION AND RELIABILITY
The Commission’s Responsibilities
The Northeast power failure called public atten.ion to the fact that the Federal Power Commission
lees not have specific authority for the reliability of
service of the interstate electric power industry, or
‘or approving the construction of facilities or the
operating practices of the systems affected by the
sower failure. The Commission has no licensing
authority over generating or transmission facilities,
)ther than hydroelectric projects which come under
ts jurisdiction including directly related transmisiion lines. The Commission has no authority to reluire adherence to reliability standards.
The responsibilities of the Federal Power Comnission are established by the Federal Power Act,
1. statute which had its origin in 1920 as the Federal
Water Power Act. The original act, now Part I of
:he statute, defines the Commission’s responsibilities
ior licensing projects for the development cf hydm:lectric power and other uses.
The Act was substantially expanded in 1935, by
the addition of Parts II and III, to include the
regulation of “public utilities” engaged in the transmission of electric energy in interstate commerce,
including the regulation of rates, and sale of electric
energy at wholesale in interstate commerce, accounting practices, issuance of securities, collection
and publication of data, and other administrative
and corporate review functions.
Part II includes a number of responsibilities pertaining to the interconnection and coordination of
electric utilities, but for the most part, actions depend upon voluntary cooperation by the industry,
or require formal complaint before action can be
taken by the Commission. The Act, which has not
been significantly amended since 1935, does not
use the specific term “reliability,” but in 202 (a)
cites “an abundant supply of electric energy
throughout the United States” as an objective, and
grants authority to the Commission, as noted herein,
to take certain actions in emergencies.
Section 202(a) of the Act sets forth major responsibilities in coordination. It directs the Commission to promote and encourage the interconnection
and coordination of power systems for the purpose
of assuring an abundant supply of electric energy
with the greatest possible economy and with regard
to the proper utilization and conservation of natural
resources. The Commission is directed to divide
the country into regional districts for the voluntary
interconnection and coordination of facilities for the
generation, transmission, and sale of electric energy,
and to make such modification thereof as in its judgment will promote the public interest. Each such
district shall embrace an area which, in the judgment of the Commission, can economically be served
by such interconnected and coordinated electric
facilities. The National Power Survey, which the
Commission published in December 1964, suggesting general guidelines for the coordinated growth
of the industry in the future, was conducted principally under the provisions of Section 202 (a).
Section 202 (b) authorizes the Commission, upon
complaint, to require a jurisdictional public utility,
after opportunity for hearing, physically to interconnect its transmission facilities with the facilities
of other entities engaged in the transmission or sale
of electric energy or to sell energy to or exchange
energy with such persons. The Commission may require interconnection, exchange or sale only if no
undue burden will be placed upon the public utility,
and the Commission may not compel the enlargement of generating facilities or any action which
would impair the ability of a utility to render adequate service to its customers. When the Commission directs an interconnection, it may prescribe the
terms and conditions to govern the inter-utility services. The limited authority to order interconnections permits the Commission in some cases to enhance reliability by providing utility systems with a
83
more reliable power supply, subject to the payment
of fair and reasonable compensation. Isolated SYSterns dependent wholly upon their own generation
have filed complaints under this provision in order
to secure backup from neighboring systems. The
section has been invoked also to secure an alternative interconnection as a means to enhance reliability and efficiency.
The Commission may not act under Section 202
(b) in the absence of a complaint. In practice,
the section has not been used by major bulk power
systems which have failed to secure voluntary interconnections with other major systems. The Commission has recommended to Congress in the past
that it be empowered to require interconnection
(subject to all the safeguards of the existing law)
on its own motion as well as upon complaints.
Section 202(c) provides that during any war, or
whenever the Commission determines that an emergency exists by reason of a sudden increase in the
demand for electric energy, or a shortage of electric
energy or of generation or transmission facilities, or
for other causes, the Commission may act upon complaint or upon its own motion, with or without
notice or hearing, to require temporary connections
and service to meet the emergency and serve the
public interest. Any emergency service is, of course,
to be paid for on a just and reasonable basis. Last
year the Commission exercised this authority to require emergency interconnection between two
neighboring utility systems where the smaller‘ system had been electrically isolated and as a result
had suffered a series of interruptions.
Section 203 of the Act provides for Commission
review of utility property transfers and mergers (except those subject to the Public Utility Holding
Company Act), affording the Commission some opportunity to consider reliabilitpof service and other
coordination problems and to require the parties to
a transaction to achieve the most satisfactory arrangement.
Sections 205 and 206 ‘Grovide for Commission review and regulation of wholesale rates and charges
for services rendered by jurisdictional public utilities. These provisions authorize Commission review
of their power pool arrangements, and consequently
provide a further opportunity to assist the parties
in strengthening the coordination of bulk power
suPPlY*
Section 207 authorizes the Commission, upon
complaint of a State commission and after oppor84
tunity for hearing, to determine the proper, adequate or sufficient service, to be furnished by a
utility so long as it does not compel the enlargement
of generating facilities or compel the sale or exchange of energy, when to do so would impair the
utility’s ability to render adequate service to its customers. Since no state commission has ever filed
such a complaint, the full scope of this section is I
uncertain.
FPC Activities in Coordination
In December 1964, the Commission published
the National Power Survey Report, a comprehensive analysis of electric systems in the United States.
The Survey projected the growth of electric requirements to 1980, and suggested general patterns for i
industry growth and coordination. It also evaluated
the many benefits attributable to interconnection I
and coordination.
I
The Survey was prepared with the collaboration
of many outstanding utility representatives from
all parts of the country and from all segments of
the electric power industry, including representatives of state commissions. It has helped to further
the economic and coordinated development of elec- t
tric power systems. The close association of many
industry leaders from all segments has promoted a
better understanding of some of the problems which I
have retarded collaboration.
With the help of an Executive Advisory Committee and six Regional Advisory Committees, the
Commission is now revising the Survey so that it ’
may continue to serve as a current reference in electric utility planning. The goal is to publish an up
dated report early in 1969. With the continuing
cooperation of the Advisory Committees and the
industry, the Commission believes the course of
studies in updating the Survey will prove to be of
substantial value. In addition to the end product
of a new Survey, much benefit will undoubtedly
accrue, as it has in the past, from the cooperative
association among the members of the Advisory
Committees and others in the industry assisting
I
them, and with the Commission and members of its
staff. It should be recognized, however, that the six
existing Regional Advisory Committees have been
established as sources of analysis and information
rather than for planning and operation. This report
urges that additional regional planning organizations be established throughout the industry for
these purposes. Such groups would be distinct tram
and she
gional ,
templa
Part1
Comm:
arbiter
mental
This k
formal
and iI
was in
vey al
years,
came i
Furthc
The
impm
opcrx
to irnl
leadin
sire a
advar
dures,
vincir
aligrlc
time,
prop<
porta
try 1,
In
sion’s
. inter1
and
time1
pro0
tions
failu
W
tDjb
indu
ities.
COUl.
regic
or ii
Con
gion
plar
tinu
pro;
to t
D determine the proper, adeervice, to be furnished by a
us not compel the enlargement
bs or compel the sale or exlen to do so would impair the
ier adequate service to its custe commission has ever filed
e full scope of this section is
and should by no means supersede the present Regional Advisory Committees. The Commission contemplates continuation of the Power Survey effort.
Partly as a result of the work of its Survey, the
Commission has been able to serve as an effective
arbiter on numerous intersystem and inter-segmental issues for the benefit of the public interest.
This has been achieved by both formal and informal means. Industry interest in the formation
and improvement of coordinating organizations
was intensified during the preparation of the Survey and following its publication. During these
years, a large number of pools and planning groups
came into existence in many parts of the country.
Coordination
1, the Commission published
gurvey Report, a comprehen: systems in the United States.
the growth of electric requireuggested general patterns for
oordination. It also evaluated
tributable to interconnection
Further Commission Assistance
The industry as a whole recognizes the need to
improve coordinated planning, construction, and
operation, and is taking steps on its own initiative
to implement more effective action. Although many
leading industry participants have expressed the desire and shown the capability for leadership in
ad\ ancing coordinating mechanisms gnd procedill-es, the course of achievement is not easy. Convincing a large number of utility participants
aligned in diverse forms of ownership takes much
time, persuasion, and understanding on the part of
proponents. We believe that the magnitude and importance of the problems which confront the industry will require greater Commission assistance.
In chapter 9 we have summarized the Commission’s recommendations for improving practices in
interconnected system planning, design, operation
and maintenance. Of primary importance is the
timely and useful formulation of organizations and
procedures which will help to achieve the suggestions which have come from our review of power
failure experiences.
We are recommending in chapter 9 that the country be divided into appropriate regions in which the
industry can conduct intensive coordinating activities. We are suggesting that regional coordinating
councils be established in which all utilities in the
region have the opportunity to participate, directly
or indirectly. We foresee the usefulness of having
Commission representation at the meetings of regional councils. The process of coordinating the
planning of utilities in the region should be continuous to keep plans updated. Plans should be
projected sufficiently in advance to be of value, alike,
to the coordinating utilities, to manufacturers and
:pared with the collaboration
utility representatives from
try and from all segments of
dustry, including representaions. It has helped to further
rdinated development of eleche close association of many
all segments has promoted a
$ some of the problems which
ration.
Executive Advisory CommitI Advisory Committees, the
:vising the Survey so that it
as a current reference in elecThe goal is to publish an up1969. With the continuing
dvisory Committees and the
rsion believes the course of
.e Survey will prove to be of
addition to the end product
Ich benefit will undoubtedly
e past, from the cooperative
e members of the Advisory
:rs in the industry assisting
lmmission and members of its
gnized, however, that the six
isory Committees have been
of analysis and information
kg and operation. This report
Iregional planning organizabroughout the industry for
roups would be distinct from
to the public and public officials concerned with
how environmental values can best be preserved or
enhanced. To serve these objectives, we are suggesting that comprehensive plans should be projected
not less than six years in advance of their intended
completion, and tentative general programs ten
years in advance. Plans should be open to modification from year to year or at intervening times as conditions arise which would make it prudent to do SO.
The Commission, concurring in the recommendations of its Advisory Committee on the Reliability of
Electric Bulk Power Supply, advocates the establishment of an interregional Council on power coordination composed of representatives from each of the
nation’s regional coordinating organizations. The
Council would exchange and disseminate information on regional coordination practices to all of the
regional organizations, would communicate to the
public, and keep state, regulatory and government
authorities informed on coordination programs, and
would review, discuss, and assist in resolving matters
affecting interregional coordination. The Council
could also assist regional organizations in supplying
data for interregional studies. Within a relatively
few years, utilities should be able to assist each other
through exchanges of capacity and energy on a
broad interregional scale.
As recommended in chapter 9, general criteria
and standards of national and regional applicability
should be established for the planning, operation
and maintenance of power systems to avoid omissions which could lead to questioned reliability.
Regulating the construction of new EHV transmission facilities including the authority to assist
utilities in securing rights-of-way when required for
approved facilities would assure that wasteful duplication of facilities is avoided; that such facilities are
planned with adequate capacity to meet the foreseeable regional transmission needs of all utilities;
that they conform with network plans tested for
stability; and that the facilities are planned and
constructed to protect aesthetic values.42 Planning
which overcomes competitive differences among
various utilities and segments of the industry will
encourage the most effective development of our
“The Commission has supported and recommended
legislation providing for Federal certification, by the FPC,
of new EHV transmission lines and hearings were held by
the Committee on Commerce, U.S. Senate, on S. 1472,
S. 2139, S. 2140,89th Congress.
85
t
bulk power systems with minimum intrusion upon
competing social values. The major problem raised
in past hearings was the fear the certification proceedings might themselves unduly delay construction of EHV facilities. The Commission, in turn,
has recognized that certification of EHV lines, standing alone, might not prove effective in realizing the
major objectives unless the proposed review, mainly
informal in nature, could begin relatively early in
the continuous planning process.
I
I
I
/
Achieving x-c
power involves
prise-the plal
maintenance 0
to develop im
methods; and
public and wit
responsibilities
mental values.
The industr
growth in the
farsightedness
for a continui
utilities can r
public with a
electric energ
thoughtful car
power system
The tentati.
in the Comm
on the North
stantiated by
in the expanc
this report. 1
have also incl
nizations, pral
tion, includin
plies to meet
future. In thj
tees, establish
dating the P
great assistan
In broad 1
has supplied
and adequat
supply failur
utilities havl
many years
u1 Northeast
Report to the
December 6,
n of EHV lines, standective in realizing the
Iposed review, mainly
;in relatively early in
is.
CHAPTER 9
CONCLUSIONS AND RECOMMENDATlONS
Achieving reliability in the supply of electric
power involves every aspect of electric utility ewerp&-the planning, construction, operation and
maintenance of electric power facilities; research
to develop improved materials, equipment, and
methods; and the relationship of utilities with the
public and with parties having special interests or
responsibilities in protecting resource and environmental values.
The industry can never be static. The dynamic
growth in the demand for electric power compels
farsightedne’ss in planning of new facilities. It calls
for a continual reappraising of ways in which all
utilities can more closely cooperate to serve the
public with an abundant and reliable supply of
electric energy at the lowest cost consistent with
thoughtful consideration to minimize the impacts of
power system facilities on environments.
The tentative conclusions and recommendations
in the Commission’s initial report to the President
on the Northeast power failure *3 have been substantiated by our further studies and are included
in the expanded findings and recommendations of
this report. The Commission’s subsequent studies
have also included a general survey of utility organizations, practices and problems throughout the nation, including the probable gdequacy of power supplies to meet unforeseen peak demands in the near
future. In this, the six Regional Advisory Committees, established by the Commission to assist in updating the National Power Survey, have been of
great assistance.
In broad perspective, the electric power industry
has supplied the nation with a highly dependable
and adequate supply of bulk power. Major power
supply failures have been relatively infrequent and
utilities have met increasing power demands for
many years with few defaults. There are many de‘* Northeast Power Failure, November 9 and 10, 1965 ; a
Report to the President by the Federal Power Commission,
December 6, 1965.
ficiencies, however, that need attention, and their
correction is becoming more important with each
passing year. The Commission’s conclusions and
recommendations apply not only to the area directly
affected by the November 1965 power failure, but
also to systems throughout the nation.
The circumstances that triggered and attended
the Northeast power failure are not unique in power
system operation. The power surge which ensued
was unusual in magnitude, but not unprecedented.
The quick opening of transmission lines from overloading and instability has occurred many times in
the operation of power systems. The isolation of
areas with deficient generation, causing a drop in
system frequency, is not a new experience, and the
total loss of system power and slow rebuilding of
boiler steam pressures to restore generation has happened before. The Northeast incident revealed
numerous system conditions which were marginal,
but still sufficient to meet ordinary disturbances.
When sharply triggered, they pyramided into an
unprecedented failure.
Upgrading the reliability of bulk power supply
throughout the nation will involve expenditures of
several billion dollars. These investments, while
large, are small in comparison with total electric
utility investments. Improving metering and display
arrangements for the benefit of system operators,
upgrading communication systems, installing underfrequency relays for load shedding, providing emergency power supplies to permit rapid restarting of
generating units and other related improvements
will cost many millions of dollars on a national scale,
but in total perspective, such expenditures are nominal. By far, the largest cost will be incurred in
strengthening transmission systems with thousands
of miles of EHV lines. Yet even here, although the
additional investment over the next eight years
might amount to as much as $3 billion, the added
annual cost, relatively, is not large. In 1975, it would
be less than two percent of the estimated cost of
supplying power to meet the projected loads.
87
The added transmission which we believe is essential for improving reliability should have large
reserve capacity to serve unforeseen requirements
and opportunities. The nation’s interconnected
power systems now span a tremendous field of present and potential diversities-diversity in power demands including errors in forecasting, in fuel costs
and the opportunities for economic energy exchanges, in water resources, in types of generation
and their proper association to meet regional loads,
in weather extremes and the threats of unprecedented localized loads, in air pollution and shifts
in generation for relief under critical circumstances,
and in the diversity of scheduled maintenance,
forced outages of equipment and a wide variety of
emergency power and transmission demands. The
nature and magnitude of the benefits of increased
transmission capability will be varied and extensive.
Through meaningful coordination of utility systems
throughout the nation, improvements made for
power system reliability can be associated with large
economic benefits as well.
If the recommendations in this report are adopted
and conscientiously followed by the electric utility
industry, it is believed that the probability of recurrence of major cascading bulk power failures can
be greatly reduced. The Commission’s specific conclusions and recommendations follow :
Formation of Coordinating Organizations
As outlined in chapter 4, a variety of planning
and pooling organizations are contributing substantially to improving the economy and reliability of
power supply in their areas, but some are too limited
in membership or in scope of activities to be effective fully. Others have overlapping responsibilities
and in many sections no effective organizations have
been formed. In general, there is a need for improved alignment and strengthening of coordinating
organizations.
1. To the extent they do not now exist, strong
regional organizations need to be established
throughout the nation, for coordinating the
planning, construction, operation and maintenance of individual bulk power supply
systems.
a. In view of the rapid growth of the industry
and the urgent need for accelerated coordination, the service areas of the .@ contiguous states should be grouped into
regions, each to be served by a coordinat-
88
ing organization which would include
representation from all utilities in the
region.
These organizations should be provided
with ample funds by member utilities and
have procedures for effective coordinating
actions. In the years ahead, utility management cannot fully discharge its responsibilities without intensive participation in
coordinating activities. All participating
utilities should respect the legitimate interests of adjoining utilities.
b. Representation of systems in regional organizations should be grouped to facilitate
progressive improvement in coordination.
Coordination of planning and operation
of bulk power supplies on a regional basis
cannot be performed efficiently by a large
number of people such as might be assembled if every utility in a region were individually represented. Qualified representatives of groups of systems will produce
effective results. Technical committees
with limited, rotating membership have
proven workable and effective.
2. A Council on Power Coordination should be
established, made up of representatives from
each of the nation’s regional coordinating
organizations to exchange and disseminate
information on regional coordinating practices to all of the regional organizations, and
to review, discuss, and assist in resolving matters affecting inter-regional coordination.
Interconnections and power exchanges ,between regions today are fairly abundant.
Many requirements and opportunities for
enhancing the reliability and economy of
bulk power supply will necessarily extend
across regional boundaries.
3. A Central Study Group or Committee should
be established to coordinate industry efforts
in investigating some of the more challenging
problems of interconnected system development.
An early coordination of ideas, efforts and
funds is needed for more effective investigations and research in planning and operation.
Today, most utilities are burdened with system problems demanding immediate solutions, making it difficult for them individually
to devote adequate attention to advancing
the development of improved design and
operatir
be perfc
universi
before I
ive rang
search
rently c
minima
Interconned
Numerous
fications shou
facilities. Son
listed below.
4. Early (
transm
The
York a
ing sys
for hi!
missior
betwee
Pennsl
netwol
from
delays
recom
North
PJM
and
shoulc
of vol
provic
and 1
system
Thr
Michi
Ohio
cling
COT
of Tl
Onta
syster
tern (
the ,
Elect
inati
5. Trar
revit
ning
shou
proc
elude
L the
vided
s and
ating
manspanon in
mating
interorgaXtate
&on.
ation
basis
large
aemindientaxiuce
ittees
have
Id be
f rom
ating
inate
prac; and
mat72.
:s bedant.
s for
1y of
stend
‘lould
forts
ngiv
lelop-
sand
stigaation.
h syssolulually
ncing
and
operating practices. Much of the work could
be performed under contract with qualified
universities and research institutions, placing
before the education committee an attractive range of technological examinations. Research investigations in electric power currently offered to educational institutions are
minimal.
Interconnected System Planning
Numerous improvements, expansions and modifications should be made in interconnected system
facilities. Some of the more important of these are
listed below.
4. Early action should be taken to strengthen
transmission systems serving the Northeast.
The peninsular relationship of the New
York and New England areas to the adjoining systems of other states and Canada, calls
for highly coordinated planning of transmission. The 500~kilovolt interconnection
between southeastern New York and the
Pennsylvania-New Jersey-Maryland ( P JM)
network, which has required rescheduling
from 1968 to 1969 because of right-of-way
delays, is urgently needed. The Commission
recommends an early strengthening of the
Northeast network and additional ties to the
PJM systems and to other systems in Ohio
and western Pennsylvania. Consideration
should be given to the need and desirability
of voltage levels higher than 345 kilovolts to
provide strong ties between the New England
and New York utilities and to adjoining
systems.
The initial interconnection in 1969 of the
Michigan utilities with those in Indiana and
Ohio will close a transmission loop encircling Lake Erie. This loop network which incorporates the western part of the system
of The Hydro-Electric Power Commission of
Ontario is being reviewed by participating
systems to determine its adequacy under system conditions similar to those suggested by
the Advisory Committee on Reliability of
Electric Bulk Power Supply. A careful examination is merited.
5. Transmission facilities should be critically
reviewed throughout the nation, and planning and construction of needed additions
should be accelerated on schedules which will
provide ample transmission capacity to meet
a broad range of potential needs for both reliability and economy as they occur.
Transmission networks and ties between
areas and regions are now deficient in numerous locations. Many systems have not participated in, or completed, area or regionwide
studies of their systems under severe impact.
Accelerated studies of transmission systems
regionally and inter-regionally are among the
industry’s foremost responsibilities.
a. Networks should remain stable under
severe disturbances.
Networks should be planned and tested
for their ability to withstand the severe
types of contingencies discussed in chapter
5. Stability analyses should include examination of both regional and inter-regional
strength.
b. The pace of construction should enable
transmission capability to lead rather than
lag behind emergency requirements.
The transfer of power from an area with
surplus generating capability to one experiencing a deficiency is frequently restricted
because of inadequate transmission capacity. The incremental cost of an adequate
network in comparison with one of marginal capability is a small part of the total
cost of supplying power.
c. Stronger transmission networks will encourage greater exchanges of capacity and
energy.
The availability of adequate transmission capacity will lead to an earlier examination of opportunities for the economic
transfer of capacity and energy within and
among regions.
6. In estimating future loads, full attention
should be given to economic trends, potential
weather extremes, and growth in special uses
of electricity in each load area.
Substantial errors can be made in relying
too heavily on projections of load growth
based primarily on past trends. More attention should be given to the probable growth
of individual components of load such as air
conditioning and home heating where extended records of past experience are of little
signiiicance.
7. Lead times for planning and constructing
major new facilities should be selected which
will avoid delays in meeting completion
89
schedules and impairment of system reliability. Extensions of as much as one to two years
in comparison with past practice may be
needed for large components.
The added complications of coordinated
planning, the time required for certifications
by regulatory bodies, the increasing difficulties of acquiring rights-of-way, delays frequently incurred in manufacturing and construction, sometimes caused by labor shortages or labor-management disputes, and the
problems in testing new EHV and very large
capacity equipment are adding, not months,
but years, to lead time requirements. In many
cases, it may be necessary to develop relatively
firm expansion plans not less than six years
in advance of need.
8. Utilities should solicit the participation of
interested parties at an early date in the
resolution of problems relating to the locat i o n a n d e n v i r o n m e n t a l ejects of new
facilities.
Utility planning involves many important
considerations. In addition to technical factors, careful attention must be given to facility
location, the preservation of aesthetic values,
the satisfactory control of air pollution and
the effects of generating station cooling
systems on aquatic environments.
9. Special attention should be paid to transmission line routing, and to switching arrangements at generating centers and at principal
interconnections in the transmission network
to provide maximum reliability in emergencies.
The economic growth of the industry will
of necessity require the concentration of
large amounts of power at generating centers and the movement of large blocks of
power on transmission rights-of-way. Particular care should be taken to avoid excessive concentration of critical circuits, which
would expose the system unnecessarily to
large loss of capability.
10. The size of generating plants, the magnitude
of area loads, and the capability of the transmission system should be kept in good
balance.
Generating capacity which is too large in
relation to the capability of the interconnecting transmission lines and the general concentration of loads in the area can impair the
reliability of supply. Transmission capacity
usefully can lead but must not lag the growth
in loads.
11. Suficient transmission should be provided to
avoid excessive generating reserve margins.
Limited transmission capacity tends to
result in generating reserve margins larger
than could otherwise be justified on either
economic or reliability considerations. With
increased transmission capability and closer
coordination in planning, utilities having
large reserves should be able to reduce them
with confidence to more economic levels.
The numerous delays which are being experienced in placing new units in commercial
operation may appear to be an element
justifying the projection of larger reserves.
These delays, however, can be overcome by
expanding the lead time for planning and
construction to take account of manufacturing schedules and expected problems in siting
or related matters.
12. A workable number of control centers should
be established in each region.
promi
econol
14. Utiliti
OPPor
compl
eratio
ET
puteri
withir
new ;
speed
eratin
lectio
data,
are i
autor
interc
econc
to m
tion
netw
meet
datic
sient
plani
netw
mit 1
anal;
distu
plica
speei
achit
At present, many systems are still controlled individually or in small groups, which
impedes coordination and, in severe emergencies, may make it virtually impossible to
take the best corrective actions. The 22
systems of the Northeast Coordinating Council are controlled by 12 dispatch offices,
six in New England and six in New York.
The Northeast power failure dramatically
underscored the inability of operators in
these many centers to have meaningful
communications with each other. Plans are
being made in the Northeast to establish two
central control points, one in New England
and one in New York. This simplification
should greatly improve coordination of these
systems for both normal and emergency
operations.
Various
were revea
utilities thl
profit fror
completed,
ciencies in
be correcte
15. Syst
13. Relay protection should be continually up-
wit1
dated to fit changing system development and
to incorporate improved relay control devices.
pro;
cleo
posj
I:
Relays are key elements in achieving reliability of bulk power supply. They are relatively inexpensive in the whole scheme of
system development. Therefore, adequacy,
quality, and readjustment should not be com-
Intercom
ran;
and
out
con
promised for the sake of practically negligible
economies.
n capacity
the growth
14. Utilities should intensify the pursuit of all
opportunities to expand the eflective use of
computers in power system planning and operation.
rovided to
e margins.
tends to
Tins larger
on either
ions. With
and closer
es having
duce them
nit levels.
being exommercial
n element
r reserves.
ercome by
nning and
anufacturns in siting
Equipment for relatively complete computerized control of power systems is not
within present capabilities. However, many
new applications are being found for high
speed digital computers in planning and operating utility systems. Among these are collections and print-out of system operating
data, including warning of conditions which
are approaching or exceeding safe limits;
automatic control of generating units in an
interconnected network to produce the most
economic increment or decrement of power
to meet changing loads; increased automation of generating plants; rapid analysis of
networks to determine line load limits to
meet assumed outages (see also recommendation 17) ; and a wide range of both transient and steady state stability studies for
planning additions to the interconnected
network. Further progress is needed to permit the reliable use of computers for on-line
analysis and control of power systems during
disturbances. Computer development and applications have advanced with phenomenal
speed and such advancement may be
achieved in a relatively few years.
!ers should
still conups, which
rere emerpossible to
. The 22
ting Counch offices,
Jew York.
amatically
erators in
neaningful
Plans are
ablish two
v England
lplification
)n of these
emergency
Interconnected System Operating Practices
I
Various deficiencies in utility operating practices
were revealed by the Northeast failure, and most
utilities throughout the Nation have been quick to
profit from it. Many remedial actions have been
completed, and others are in progress. All deficiencies in the categories enumerated below should
be corrected as soon as possible.
15. Systems control centers should be equipped
oually uppment and
ontrol de-
with display and recording equipment which
provide the operator at all times with as
clear a picture of system conditions as is
possible.
ving reliar are relascheme of
adequacy,
ot be com-
Desirable displays include narrow and wide
range indications of system frequency, tieline
and principal transmission line flows, lines
out of service, positions of switches, overload
conditions, generating units in service, unit
and plant outputs, available spinning reserve
and current rate of response, voltages and
frequency 44 at key points, area control
error 4j and appropriate alarms.
.16. Communication systems should be supplied
with continuously available power in order
that information on system conditions can be
transmitted correctly to control centers during system disturbances.
System data transmitted by equipment
supplied with erratic system power during
a disturbance will furnish computers and operators with misleading information. Whenever power supply for communications equipment deviates beyond specified limits, the
equipment should be automatically and instantaneously switched to an emergency
power source.
17. Control centers should be provided with a
means for rapid checks on stable and safe capacity limits of system elements.
The necessity for isolating a line or substation or dropping a generating unit, either
in an emergency or for planned maintenance,
can result in major shifts in network power
flows. Rapid security checks to determine
that various elements will be operated within
safe limits under such modified conditions
are essential to prevent unsafe loading. Rapid
security checks are now feasible through the
use of digital computers.
18. Spinning reserves should be able to respond
quickly to a level which can be sustained in
meeting emergency power demands.
The effectiveness of spinning reserve is
measured by its rate and level of sustained
response rather than the sum of surplus capacities in generating machines connected to
the load. Rapid response normally requires
that the reserve be distributed among a large
number of units.
19. Coordinated programs of automatic load
shedding should be established and maintained in areas not so equipped to prevent the
total loss of power in an area that has been
separated from the main network and is deficient in generation. Load shedding should
“In the event of an area separation from the network.
“Deviation of an area’s generation from power supply
commitments.
91
be regarded as an insurance program, however, and should not be used as a substitute
for adequate system design.
Strongly interconnected systems should be
able to meet emergencies without loss of load.
Every utility, however, should have a wellorganized load shedding program as an emergency backup. Since it is not possible to be
sure of the boundaries of separation that may
occur from a severe disturbance, it is important that systems adopt coordinated programs
of load shedding. To fail to do so is to risk
imposing inequities among the customers of
various systems, creating an imbalance in the
flow of supporting power, and reducing the
effectiveness of the programs. The effect of
these programs should be carefully checked
for a variety of unusual loading conditions
during an assumed severe disturbance. Where
appropriate to a particular area, procedures
for automatic generation dropping upon the
loss of a principal transmission artery should
also be considered.
The Commission recommends that all
areas have a coordinated program of automatic load’ shedding as an emergency backup
to strong interconnections among systems.
Automatic load shedding will be much more
effective in emergencies than a manual program. Arrangements should provide for shedding load in total amounts at least equal to
the largest conceivable loss of power supply
in appropriate increments as system frequency declines. A thoughtful selection of
loads or load areas for the various increments
of load relief is essential. Some revisions in
circuits may be needed. Occasional rotation
of areas may be helpful. Each utility should,
in cooperation with state commissions or
other appropriate authorities, establish procedures for informing the public of its load
shedding program.
20. Plans should be made and to the extent feasible, tested for the quick isolation of generating units to maintain them in operation if
collapse of system power is imminent.
Some units can continue to operate under
very light loading, supplying power only to
their own auxiliaries. Others cannot continue
in satisfactory operation when serving loads
less than 20 to 30 percent of rated output.
92
Switching procedures must be carefully
planned to isolate appropriate units quickly
in an emergency. Units maintained in isolated operation will be able to pick up loads
rapidly following correction of power failure
problems. Smaller units may be isolated primarily to assure that restarting power for
larger units in the plant or adjacent plants is
available.
21. Emergency power should be auailable at all
thermal generating stations to prevent damage to turbo-generators during rundown if
system power is lost, and for lighting and control system operation.
To prevent damage to units, pressures
must be sustained on bearing lubrication and
hydrogen sealing systems. Emergency power
should be provided to operate the pumps of
these systems, to operate turning gear, to keep
the control system operable and to provide
lighting in the control room and other critical areas.
22. Auxiliary power should be available to the
principal thermal generating plants of a system to enable rapid restarting if system power
is lost and units are forced to shut down.
Power required to drive the auxiliary
equipment of a thermal generating station
averages 5 to 6 percent of the station’s output. Provision of emergency power for the
operation of auxiliaries during plant startup
can save hours of time in service restoration
if power is lost over a wide area.
23. Thorough programs and schedules for operator training and retraining should be vigorously administered.
Many operators become highly skilled in
handling the day-to-day problems of system
operation, including commonly occurring
system disturbances, but more attention
should be devoted to rehearsing procedures
for meeting severe disturbances from a wide
variety of potential contingencies. New technical skills are required in monitoring modern
power systems. Special switching requirkments to meet temporary or unusual conditions must be thoroughly checked and
rechecked. Close coordination among the
planning, operating and maintenance staff, is
indispensible.
Interconned
Practices
24. Program
strongl:
than re
swit
lays, cc
PlY sys
many
eratior
a rigor
are inc
25. Manu,
dissem
ures i
users c
Thi
dissen
bulk 1
on sek
26. The i
for te
sched
opera
sor
probl’
coord
Criteria a
27. Crilz
tion,
syster
gui4ic
w:
the
plan
of 01
and I
dust]
ning
. syste
sent
neig
Defense
28. Altk
can
fails
atta
?
Interconnected System Maintenance
Practices
24. Programs of system maintenance should be
strongly directed toward preventive rather
than remedial maintenance.
Switch gear, transformers, protective relays, communications, emergency power supply systems, supervisory control systems, and
many other elements involved, in system operation should be tested and maintained on
a rigorous schedule, whether remedial actions
are indicated or not.
25. Manufacturers and utilities should promptly
disseminate information on troubles or failures of equipment for the information of
users of similar equipment.
The Federal Power Commission will also
disseminate the information reported to it on
bulk power outages, and its special reports
on selected power interruptions.
26. The isolation of any elements of the system
for testing, repair, or replacement should be
scheduled by, or receive the clearance of, the
operating department.
Some of the power failure reports indicate
problems resulting from a lack of internal
coordination of work plans.
Criteria and Standards
27. Criteria and standards for planning, construction, operation, and maintenance of power
systems should be formulated for general
guidance.
With the expansion of electric loads and
the interconnection of power systems, the
planning, operating and maintenance policies
of one system increasingly affect the quality
and cost of service of its neighbor. The industry needs minimum standards for planning, construction, and operation so that each
system can be reasonably assured that its own
service will not be adversely affected by its
neighbors’ policies.
Defense and Emergency Preparedness
28. Although severe damage to power systems
can be inflicted by enemy attack, cascading
failures should not follow as a consequence of
attack on a strong bulk power system.
The steps which we recommend be taken
to improve ,the reliability of bulk power supply will also place the utility systems of the
United States in a better position to resist
widespread failure if subjected to enemy attack. The nation’s utilities are organized and
generally have adopted programs of defense
readiness by providing emergency supplies,
fallout shelters, mobilization procedures, and
property protection prescribed by the Defense
Electric Power Administration of the Department of the Interior, and the Department
of the Army. Utilities generally have security
programs which are adequate for normal requirements, but many, with further guidance
from defense authorities, should strengthen
their preparedness for security control under
enemy attack.
29. All levels of government appropriately should
establish requirements for emergency power
sources for services essential to the safety and
welfare of the public, and ensure the availability of such facilities.
Precautions should be taken not only
against the possibility of a future area-wide
power failure, but also the more likely occurrence of local outages such as caused by
severe storms. Since the November 1965
power failure, Federal agencies and many
state and local governmental bodies have
taken steps to lessen the impact of future
power interruptions. More than half of the
states now require local auxiliary power for
certain critical loads. This practice should be
extended, under carefully considered criteria
to assure essential emergency service while
safeguarding against unwarranted duplication of expensive generating facilities. Accordingly, the Commission urges state, county
and local government agencies to encourage
and direct by legislation, regulation and other
means, the planning and installation of
needed auxiliary power facilities to provide
essential services for the safety and welfare
of the public.
30. Utilities should cooperate with appropriate
public oficials and customers in planning and
maintaining customer standby facilities to
assure service to critical loads in the event of
emergency.
Even though the improvements recommended herein will do much toward preventing further widespread power failures, the
93
possibility of interruptions remains. Localized
failures will continue to occur from storms,
equipment breakdown and other causes. The
complete dependence of many important public services upon electric power requires the
appropriate provision of emergency power
supplies. These services typically include hospitals, police and fire departments, sewer and
water plants, transportation systems and terminals, communications facilities, and emergency lighting and elevator service in public
or other multi-story buildings which normally
contain many people. Many such facilities in
the Northeast were not equipped with emergency power. Others had standby sets that
did not operate because they had not been
tested and maintained or because informed
operators were not available to start them.
The Commission urges that utilities and
agencies responsible for essential services work
together in the proper planning and maintenance of emergency power facilities.
Manufacturing and Testing Responsibilities
31. Manufacturing capacity of electrical equipment suppliers should be expanded on a continuing basis to meet future needs.
A deficiency in manufacturing capacity
can delay production of needed equipment,
with detrimental effects on the reliability of
bulk power supply. The need for adequate
electrical equipment is of such importance
that risk of serious shortages must be avoided.
The Commission recommends that utilities
study the long-range outlook carefully, and
that manufacturers take appropriate actions
to ensure that sufficient manufacturing
capability will be available to allow for timely
delivery of equipment. Better dialogues on
projected requirements between utilities
and manufacturers is needed and -will be
aided by improved planning and coordinating procedures suggested in this report.
32. Facilities are needed in the United States for
more extensive testing of EHV equipment.
Resources for testing major items of electrical equipment are limited primarily to the
laboratories of two manufacturers which are
not adequate in some respects for subjecting
new equipment to tests which fully represent
actual service conditions.
94
.
The Commission urges the early consideration by the electric utility industry of its future needs for high-voltage testing facilities,
the development of plans, the required support by utilities and manufacturers and the
early construction of appropriate facilities so
that the reliability of future bulk power supplies will not be impaired unnecessarily by
lack of proper testing capabilities.
Increased Need for Technical Proficiency
33. The industry should take advantage of every
opportunity to present to young people tlze
full challenge of modern power systems engineering.
Shortages of technical talent represent one
of the more serious problems facin~g the electric utility industry. The electric utilities have
not kept up with competition in attracting
technical talent, and the mounting shortage
of strong technical staffs poses a threat to the
future reliability of the nation’s power supply. Utilities should work more closely with
educational institutions to develop and sponsor appropriate research activities, to utilize
cooperative work programs for students and
industry assignments for educators, and to
exploit fully the opportunities for new and
sophisticated research and development
programs.
Power System Practices in Other Countries
34. Power systems in other countries arc experiencing similar problems in the planning and
operation of power systems. System clesign
and operating practices in other countries arc
generally similar to those in the U.S. The
practice of exchanging technical information
on improvements in power system equipment
and operations among other power consuming n a t i o n s s h o u l d b e c o n t i n u e d a n d
expandea.
The circumstances of the Northeast power
failure have alerted power system engineers
in every country having a well-developed
power supply program. There are no systems
abroad which match the scale of interconnection, wide variation in load density and
pluralistic composition that exist in the
ic
United ,C
having M
however
deeply (
portancc
power.
Actions takf
ity of power f:
are progressin
The Commis
strengthened
but also to as:
be strongly st
emergencies, 1
The Comr
tention of th
of coordinate
provide the r
that most ef
The Corn
of the Execl
ges tions in t
tion of the
review of tl
Committee
Supply and
herewith.
The Rei
cially helpj
tailed infor
in responst
by the Cc
pendix A
We also
R. Acker,
ordinatin,g
Chairmar
Committc
Jack K.
c. P. Alr
Cornmitt
their dets
We wi
report of
necessari
lectively,
:onsideraof its fufacilities,
lired sup: and the
rcilities so
)wer supssarily by
diciency
: of every
aople the
stems cn-
esent one
the elecities have
attracting
shortage
:at to the
leer supsely with
:nd sponto utilize
lents and
#, and to
new and
slopment
wntries
c cxperiaing and
n d,esign
Itries arr
is. Thea
umation
pipment
consum.ed a n d
st power
:ngineers
eveloped
) systems
.nterconlsity and
i n the
United States. We find among all countries
having well-developed electric power systems:
however, a common understanding and a
deeply concerned appreciation of the importance of reliability in the supply of electric
power.
1..h
g.
Q
.x.
-Yc
Actions taken by utilities to reduce the probability of power failures in the Northeast or elsewhere,
are progressing. These must be pursued vigorously.
The Commission is concerned that networks be
strengthened not only to minimize power failyres,
but also to assure that every area of the nation can
be strongly supported by adjoining utilities in any
emergencies, whatever they may be.
The Commission will continue to direct the attention of the industry to the timely development
of coordinated procedures and programs which will
provide the nation with a bulk power supply system
that most effectively incorporates the elements of
reliability and economy. The Commission believes
that these objectives can best be sought by:
0 stronger coordination mechanisms,
0 comprehensive planning of power resources
in each region and among regions,
0 the construction of transmission facilities that
will meet the requirements of reliability and
economy.
Despite the long record of outstanding service
that has characterized the supply of electric energy
in the United States, the industry is faced squarely
with the challenge that much remains to be done
if the nation is to have the reliability it requires,
deserves and demands. The industry must act, not
only to prevent cascading failures, but to assure
freedom from the hazards of marginally sufficient
power supplies. In some aspects, the improvement
process is time consuming and requires careful
planning, but with the concerted effort of all, these
goals can be achieved before 1975.
ACKNOWLEDGMENTS
The Commission is greatly indebted to members
of the Executive Advisory Committee for their suggestions in the formulation of programs of investigation of the Northeast power failure, and for their
review of the report of the Commission’s Advisory
Committee on Reliability of Electric Bulk Power
Supply and early drafts of the Commission’s report
herewith.
The Regional Advisory Committees were. especially helpful to the Commission in assembling detailed information on industry practices in reliability
in response to the several lines of inquiry suggested
by the Commission staff paper included in Appendix A of this report.
We also take this opportunity to thank Mr. Ernest
Ii. Acker, Chairman of the Northeast Power Coordinating Council and Mr. Philip Sporn, past
Chairma; of the Commission’s Executive Advisory
Committee, for their special assistance, and Messrs.
Jack K. Busby, Chairman, and T. J. Nagel and
C. P. Almon, Jr., Vice Chairmen of the Advisory
Committee on Reliability of Bulk Power Supply, for
their detailed review of this report.
We wish to note, however, that Volume I is the
report of the Commission and the staff and does not
necessarily represent the views individually or collectively, of those we acknowledge here.
Members of the Executive Advisory Committee
are as follows :
EXECUTIVE ADVISORY COMMITTEE
Chairman: Lee F. Sillin, Central Hudson Gas &
Electric Corporation
Members :
Thomas G. Ayers, Commonwealth Edison
Company
David S. Black, Bonneville Power Administration
Donald S. Kennedy, Oklahoma Gas & Electric
Company
A. H. McD0wel1,“~ Virginia Electric & Power
Company
Ii. J. McMullin, Salt River Project Agricultural Improvement & Power District.
Harry L. Oswald, Arkansas Electric Cooperative Corporation
S. L. Sibley, Pacific Gas & Electric Company
C. H. Whitmore, Iowa-Illinois Gas & Electric
Company
Harry G. Wiles,47 Kansas Corporation Commission
95
Members of the Regional Advisory Committees
are as follows :
NORTHEAST REGIONAL ADVISORY COMMITTEE
Chairman: Howard J. Cadwell, Western Massachusetts Electric Company
Members :
Ernest R. Acker, Northeast Power Coordinating Council
W. S. Chapin, Power Authority of the State
of New York
Walter N. Cook, Vermont Electric Cooperative, Inc.
T. C. Duncan, Consolidated Edison Company
of New York, Inc.
William H. Dunham, Central Maine Power
Company
J. Emerson Harper, Department of the Interior
William F. Hyland, New Jersey Board of Public Utility Commissioners
F. H. King, Holyoke Municipal Gas & Electric
Department
M. H. Pratt, Niagara Mohawk Power Corporation
Edwin H. Snyder, Public Service Electric &
Gas Company
Stephen R. Woodzell, Potomac Electric Power Company
SOUTHEAST REGIONAL ADVISORY COMMITTEE
Chairman: W. B. McGuire, Duke Power Company
Members:
E. B. Crutchfield, Virginia Electric & Power
Company
Thomas R. Eller, Jr.,48 North Carolina Utilities
Conmiission
R. H. Fite, Florida Power & Light Company
Shearon Harris, Carolina Power & Light Company
Charles W. Leavy, Southeastern Power Administration
E. V. Lewis, Central Electric Cooperative, Inc.
J. B. Thomason, South Carolina Public Service
Authority
Alvin W. Vogtle, Jr., The Southern Company
James E. Watson, Tennessee Valley Authority
A. M. Williams, Sr., South Carolina Electric &
Gas Company
96
SOUTH CENTRAL REGIONAL ADVISORY COMMITTEE
Chairman: Gordon W. Evans, Kansas Gas and
Electric Company
Members :
C. W. Anthony, Oklahoma Gas & Electric
Company
W. M. Brewer, Middle South Utilities, Inc.
B. B. Hulsey, Texas Electric Service Company
Czar D. Langston, Jr., Oklahoma Association
of Electric Cooperatives
Charles M. Matthews, Greenwood Utilities
Frank W. May,4? Missouri Public Service Commission
G. E. Richard, Gulf States Utilities Company
G. E. Schmitt, Lower Colorado River Authority
J. R. Welsh, Southwestern Electric Power
Company
Douglas G. Wright, Southwestern Power Administration
EAST CENTRAL REGIONAL ADVISORY COMMITTEE
Chairman: D. Bruce Mansfield, Ohio Edison
Company
Members :
J. H. Campbell, Consumers Power Company
John P. Gallagher, Piqua Municipal Power
Plant
E . L . Lindseth,4’ The Cleveland Electric
Illuminating Company
Wells T. Lovett, Kentucky Public Service
Commission
Walter J. Matthews, Public Service Company
of Indiana, Inc.
F. J. McAlary, Allegheny Power System, Inc.
T. J. Nagel, American Electric Power Service
Corp.
H. L. Spurlock, East Kentucky Rural Electric
Cooperative
WEST CENTRAL REGIONAL ADVISORY COMMITTEI
Chairman: J. W. McAfee, Union Electric Cornpan:
Members :
G. R. Corey, Commonwealth Edison Cornpan.
H. N. Ericksen, Nebraska Public Power Systen
E. Ewald, Northern States Power Company
J. L. Grahl, Basin Electric Power Cooperative
A. Gruhl, Wisconsin Electric Power Compan]
D. M. Heskett, Montana-Dakota Utilitie
Company
George A. Lewi
Dick-A. Witt,
mission
A. Van Wyck, !
W EST REGION‘
Chairman : Frank
Electric Compan)
Members :
Marshall L. B
Company
P. A. Bland
Company
J. F. Bonner, I
J. J. Bugas, Cc
Inc.
Howard Elmo
of Chelan C
Kansas Gas and
George A. Lewis, Bureau of Reclamation
Dick A. Witt, Iowa State Commerce Commission
A. Van Wyck, Illinois Power Company
Gas & Electric
W EST R E G I O N A L A D V I S O R Y C O M M I T T E E
SORY
COMMITTEE
Ith Utilities, Inc.
Service Company
homa Association
wood Utilities
blic Service ComI tilities Company
lo River AuthorElectric Power
stern Power AdDRY C O M M I T T E E
1, Ohio Edison
Power Compaq
Iunicipal Power
:veland Electric
Public Service
ervice Company
k
yer System, Inc.
C Power Service
Y Rural Electric
FRY C O M M I T T E E
ectric Company
,dison Company
C Power System
fer Company
rer Cooperative
‘ower Company
akota Utilities
Chairman : Frank M. Warren, Portland General
Electric Company
Members :
Marshall L. Blair, Washington Water Power
Company
P. A. Blanchard, Utah Power & Light
Company
J. F. Bonner, Pacific Gas & Electric Company
J. J. Bugas, Colorado Ute Electric Association,
Inc.
Howard Elmore, Public Utility District No. 1
of Chelan County
Bernard Goldhammer, Bonneville Power Administration
Frederick B. Holoboff,47 California Public
Utilities Commission
Emil Lindseth, U.S. Bureau of Reclamation
S . B. Nelson,47 Los Angeles Department of
Water & Power
Robert P. O’Brien, Southern California Edison Company
L. R. Patterson, Public Service Company of
Colorado
D. W.. Reeves, Public Service Company of
New Mexico
4G Deceased.
” Indicates members who no longer are active in the
associations named and have terminated their participation with their committees.
” Resigned from committee.
e
APPENDIX A
GENERAl. SURVEYS OF THE RELIABILITY CHARACTERISTICS OF
U.S. POWER SYSTEMS
Introduction
The Federal Power Commission, on January 10,
1966, established six Regional Advisory Committees
to assist it in updating the National Power Survey
alld in compiling important data relating to current practices in the design and operation of electric utility systems throughout the nation. In June
1966, the FPC staff issued criteria for surveys of
six areas of design and operation related to the
reliability of bulk power supply. The staff paper
outlining these criteria follows.
Criteria for General Surveys by ,Regional
Advisory Committees of Important Power
System Design and Operating Practices
Relating to Reliability of Bulk Power Supply
Surveys of certain practices in system design and
operation which have a bearing on the reliability
of bulk power supply have been scheduled by the
Commission for the early attention of the Regional
Advisory Committees. This staff paper enumerates
items suggested for the surveys, and general specifications for the scope of the inquiries. Because of the
early need for this information, the Commission is
asking that the surveys and evaluations by each of
the Regional Committees be concluded by September 1, 1966.
The several items suggested for investigation are
as follows :
1. Surveys of the system design studies relating
to stability under severe disturbances.
2. Practices in load and generation reduction
under disturbed system operating conditions.
3. Practices in providing spinning reserves, and
design and experience data on response of
spinning reserve.
4. Provisions for rapid restoration of system
service.
5. Practices and plans for use of digital computers as aids or controls in improving system
power supply reliability and system stability.
6. A summary of incidents in which a major outage of equipment occurred but there was no
service interruption because of support
through interconnections.
The Regional Committees should summarize
each one of these investigations in a separate paper.
The information included will also be made available to the Advisory Committee on the Reliability of
Bulk Power Supply and to the Executive Advisory
Committee.
Survey of Sfability Sfudies
It is the purpose of this survey to examine the extent to which interconnected systems have analyzed
the transient stability of their networks under assumed very severe impacts. To this end, it is suggested that those studies be enumerated and
described which are of the greatest magnitude from
the standpoint of area of interconnection and severity of imposed disturbing conditions. It is presumed,
for example, that in each region studies may have
been made for three or four areas within the region
or possibly for the entire region and that such events
as a total generating plant or a major corridor of
transmission or a principal substation .has been assumed to be interrupted. If studies of this magnitude
have not been made, it would be .helpful to have a
description of those studies which most nearly approach this scale of examination. It is not intended
that the survey encompass a listing or description of
the many steady state and transient analyses which
simulate normal steady state operation or which
test transient conditions of a more routine nature.
Information can be supplied in whatever narrative, tabular or other form is convenient and understandable. However, it will be useful to have a designation of the group of utilities, the pool, or other coordinating organization or entity responsible for the
99
studies, a discussion of the types of incidents selected,
whether the studies embrace current or include
future loading system conditions and an appraisal of
the effects of the assumed incidents on system
performance.
Practices for Emergency Load and Generation
Reduction
The scope of this survey includes practices in load
reduction under disturbed system conditions, either
through programs of manual or automatic load
tripping or through manual or automatic voltage reduction; and any procedures for automatic disconnection of generators simultaneous with major loss
of load. The survey reports could be made by coordinated systems or pools insofar as the coordinated
group employs common practices. For each utility,
system, or group surveyed in the region, the following information is desired :
a. Description of any emergency load reduction
program, including percentage of load shedding at various levels of frequency or other
methods of defining amounts of and corresponding conditions for load reduction as
appropriate.
b. Practices and policies in maintaining or opening interconnections between utilities operating at abnormal frequencies following isolation of the group from the interconnected network. If policies are not defined, this should
be so stated.
c. Applications of automatic generator tjpping
concurrent with major loss of load.
d. Number of different occasions when load shedding was utilized during 1965 by the utility or
group reporting.
e. How completely does this survey cover the individual utilities in your region? (List individual entities covered by survey.)
Practices in Spinning Reserve
Spinning reserve is the capacity of generating
equipment-connected to the load which is in excess
of the load being carried. The intent of this survey
is to obtain information on general practices among
utilities, or coordinating groups where uniform
practices are in effect, in planning spinning reserve.
Each system or group of systems normally is composed of a variety of types of generating facilities,
some of which are loaded partially and some fully.
The response can be in narrative form using tabulations if helpful, indicating the entity for which the
100
analysis is presented, the general composition of
generation, the variation in loading, the rate of response under emergency conditions in terms of
actual experience, or if not available, in terms of estimated performance. Information is also desired
on the change in system output that would occur
with a 0.1 cycle per second change in frequency,
based on normal load distribution, and plant operating practice; and the time required for the system or group of systems to pick up ten percent of its
rated maximum capacity. If interruptible loads are
included as a part of the “spinning reserve” allowance, what are the procedures and what is the time
required for effecting interruption? What are the
typical practices in distributing spinning reserve
among units? What reliance is placed upon interconnections with other systems, upon spinning reserve held in the largest generating unit of the system or other criteria? Is quick-starting capacity
which is not actually on the line relied upon as a
part of spinning reserve?
Restoration of System Service
It is recognized that practices for rapid restoration of service in the event of a total loss of system
power or when such loss of system power is imminent
vary widely among systems depending upon individual circumstances. Some utilities rely upon their
interconnections with other systems for the supply
of emergency restarting power. Others rely upon
hydroelectric plants within their own systems from
which power can be transmitted to stations in need
of startup assistance. Still others have made provisions at their steam stations for quick-starting sources
of power, such as diesel or gas turbines, which can
be used for operating station auxiliaries. It would be
helpful in responding to this survey to receive narrative reports from principal systems or groups of
systems or pools which have established a consistent
practice, which present specific information on the
provisions made and an evaluation of the effectiveness of these provisions for the area should a widespread power failure occur in the area.
Practices and Plans for Use of Digital Computers
Most digital computer applications today are
thought to be in the areas of load flow analysis,
transient stability studies, and economic dispatch.
However, at least some thought has been given to
the possibilities of using digital computers on a realtime basis for consolidation or coordination of current information on system conditions so that oper-
ators may takr
for system secu
elements of the
reliability of p
would seek out
along the lines
developed plan
they may not E
year or so.
Interrtiptions
1
This is inter
of important si
past three to f
have played a
interruption. A
currence in eat
be of significal
must be approl
nections utilize
example, to inI
loss of a genera
tern carrying a
though some 01
the interconnec
system would h
without intercc
Descriptions in
sufficient infon
indicate the i
interconnectior
The results
visory Commit
for investigatic
sections. Infon
interruptions a
port appears in
General Sur
a. Survey of S
The problen
tern has been r
rent generators
1 composition of
~g, the rate of reons in terms of
ble, in terms of esbn is also desired
that would occur
1ge in frequency,
> and plant operuired for the systen percent of its
ruptible loads are
lg reserve” allow1 what is the time
n? What are the
spinning reserve
laced upon interlpon spinning re~g unit of the sysstarting capacity
relied upon as a
Service
for rapid restorajtal loss of system
rower is imminent
nding upon indies rely upon their
ns for the supply
Others rely upon
)wn systems from
o stations in need
iave made provi:k-starting sources
rbines, which can
iaries. It would be
ey to receive narems or groups of
lished a consistent
lformation on the
n of the effectivcea should a widerea.
igital Computers
ators may take quicker or more effective action,
for system security checking, or even for actuating
elements of the system in such a way as to increase
reliability of power supply. The survey proposed
would seek out and describe any such applications
along the lines of the second group, and any well
developed plans for such applications, even though
they may not be expected to be in operation for a
year or so.
Interru’ptions Avoided Through Interconnected
Support
This is intended to be a comprehensive survey
of important situations which have occurred in the
past three to five years in which interconnections
have played a major role in preventing a service
interruption. A short description of each such occurrence in each region would be appropriate. To
be of significance, the magnitude of the incident
must be appropriate to the strength of the interconnections utilized. It would not be impressive, for
example, to include an incident that involved the
loss of a generating unit of 100 megawatts on a system carrying a total load of 3,000 megawatts, even
though some of the support would have come from
the interconnections. Outage incidents in which the
system would have been adequate to absorb the loss
without interconnections should not be included.
Descriptions in great detail are not intended but
sufficient information should be included to clearly
indicate the importance of the part played by
interconnections.
The results of the surveys by the Regional Advisory Committees of the first five items suggested
for investigation are summarized in the following
sections. Information pertaining to the survey of
interruptions avoided through interconnection support appears in chapter 3 of this report.
General Surveys
a. Survey of Stability Studies
The problem of stable operation of a power system has been recognized ever since alternating current generators have been operated in parallel, and
has been under continuous study by power system
engineers since the beginning of the industry.
A technical discussion of power system stability
is contained in Appendix B of Volume II, Advisory
Committee Report on Reliability of Bulk Power
SUPPlY*
Longhand calculations to determine the effects
of most changes in a complex electric system are SO
tedious and time consuming as to be virtually impossible. Network analyzers were generally used for
many years, but the advent of the large-scale, highspeed digital computer within about the last ten
years has provided a better means of making studies
of large electric systems.
Since the Northeast power failure, most stability
studies have considered somewhat more severe conditions, and have examined more extensive areas,
than in the past. Also, power networks in virtually
all areas of the country have been examined for
expected performance during severe disturbances.
Most of the stability studies reported in the
surveys indicated that the systems were stable for the
loss of a large generating plant or a major transmission line. However, if the study were carried
further to include the loss of a second line, generally
the result was further cascading of lines and the
isolation of areas.
In some instances, there are needs for more comprehensive studies, encompassing larger geographical areas and time periods farther into the future,
than those which have been used in the past.
Furthermore, the length of the interval for detailed
analysis following initiation of a disturbance is being
increased by the study groups in some areas, and
others may profit by analyzing system performance
for longer periods than the first swing cycle used
in most studies in the past.
The following tabulation lists the major stability
studies reported in each of the Federal Power Commission’s six regional study areas. Included in this
tabulation are the systems involved in each study,
the purpose of the study, the conditions examined,
and the conclusions reached.
.ations today are
Iad flow analysis,
:onomic dispatch.
has been given to
nputers on a realordination of curtions so that oper101
TABLE A-l .-Stabili~
Studies
NORTHEAST
Sponsor of Study
Northeast Interconnected System Studies Group.
1966
Peak
Load
IMW
!9, ooo
argest
Jnit in
ervice
1966
iecond
argest
I Jnit in
Liervice
1966
--
l,ooo
400
Eastern New York-New England Systems Study Group.
NPCC Task Force on System
Studies.
argest
Jnit in
;ervice
1970
,argest
Jnit in
lervice
1970
Principal Transmission Voltage
in Service 1966
I
Principal Transmission Voltage
in Service 1970
295
Utilities C
I
345-230
500-345-230
1,169
345-230
500-345-230
1,069
345-230
500-345-230
640
230-138
500-230
I
Allegheny Power System and
General Public Utility Systern.
REGION
CANUSE Syst
,
CANUSE Syst
CANUSE Syst
4
Allegheny Pov
General Public
I
500-345-230
I
400
Pennsylvania-New JerseyMaryland Power Pool.
363 ,
363
865
865
230
500-230
AEP-APS-VEPCO-PJM. . . .
58C
57c
865
865
345-230-138
765-500-345
ESURPA-PJM-APS. .
13,600
345-230
Utilities in N.’
Penna-NJ-Md
Allegheny Pou
I
Penna-NJ-M1
American Elt
Allegheny PO
Virginia Elec
Penna-NJ-M
267-7
1 .-Stability
Studies
<THEAST
REGION
II TransVoltage
ice 1970
-
Utilities Covered by Study
Purpose of Study
Conditions Studied and Conclusions
Simulate sequence of events during
the early period of the Northeast
blackout.
Simulate sequence of events to final
shutdown of the “island.”
To study cases of instability developed in Northeast Interconnected
System Studies Group with generation and transmission additions to
1968.
Study made by General Electric
Company with APS and GPU to
determine whether or not the systems would be stable for the loss of
a large generator under realistic
operating conditions.
To determine the problems that
result from the loss of Consolidated
Edison’s Ravenswood #3-1000 Mw
generating unit.
Discussed further in report. See Volume
III.
-
-345-230
CANUSE Systems. . . . . . . . . . . . . . . .
-345-230
CANUSE Systems.. . . . . . . . . . . . . . .
-345-230
CANUSE Systems. . . . . . . . . . . . . . . .
500-230
Allegheny Power System. . . . . .
General Public Utility System.
. .
-345-230
Utilities in N.Y. State.. . .
Penna-NJ-Md Pool.
Allegheny Power System.
. .
500-230
Penna-NJ-Md Power Pool. . .
. .
500-345
American Electric Power System
Allegheny Power System.
Virginia Electric & Power Co.
Penna-NJ-Md Pool.
267-7810-67--s
To study the transient stability of
the PJM 500-Kv system which
includes Keystone (1800 Mw) and
Muddy Run (800 Mw) plants.
To investigate the region for possible
stability problems for loss of any
transmission on same right-of-way,
major substation, or generating
station.
Discussed further in report. See Volume
III.
Discussed further in report. See Volume
III.
The study made in 1963 found no operating difliculties.
Studies made in 1965 and 1966 indicated
the necessity of operating the unit at less
than full load until additional transmission already under construction was
installed.
This study covered three-phase, two-phase,
and single-phase faults at critical locations on the Keystone 500-Kv system for
1968. It includes an evaluation of the
swing problems that occur on the underlying 230-Kv network as a result of
swings of the Keystone generators. The
system was found to be stable for threephase faults with normal clearing and
for single-phase faults with delayed
clearings.
This study of the 1968-72 period includes
both transient stability and post-transient
load flow runs during the build-up of
generation at Keystone (1809 mw),
Homer City (1309 mw), and Conemaugh
(1609 mw) in PJM, atPort Martin (1000
mw) in APS, and Mt. Storm (1140 mw)
in VEPCO.
103
.
TABLE A-l .--Sfabik
SOUTHEAS’
Largesi
Unit ir
Service
1966
400
Seconc
Larges
Unit ir
Service
1966
40(
Large
Unit
Servi
1971
7:
Secant d
Largerrt
Unit i n
Servics e
1970
531 3
Studies-Continued
Principal Transmission Voltage
in Service 1966
Principal Transmission Voltage
in Service 1970
23t
236
REGION
Utilities Cove
Florida Power Car
Florida Power &
City of Jacksonvil
City of Orlando.
Tampa Electric C
c
Southern Services, Inc. . . . . .
27f
27C
544
544
230
230
Alabama Powa
Georgia Power
Gulf Power Co
Mississippi POW
Southern Elect
TABLE
A-I.-Stabi&
SOUTHEAST
lal Trans1 Voltage
rice 1966
23G
230
Principal Transmission Voltage
in Service 1970
230
230
Studies--Continued
REGION
Utilities Covered by Study
Purpose of Study
Florida Power Corp.. . . . . . . . . . . .
Florida Power & Light Co.
City of Jacksonville.
City of Orlando.
Tampa Electric Company.
To assure that the transient stability
problems associated with the loss of
large generating units will not adversely alTect service.
Alabama Power Co.. . . . . . . . . . . . .
Georgia Power Co.
Gulf Power Company.
Mississippi Power Co.
Southern Electric Generating Co.
Transient stability studies are made
routinely for planned generating
unit additions.
Conditions Studied and Conclusions
I. Studies for the winter of 1964-65 and
1965-66 considered single contingencies
of an outage of the largest generating
unit. It was concluded that the peninsula
of Florida would not have transient
stability problems due to the sudden loss
of the largest unit in major load areas.
2. Studies for the winter of 1967-68 are
being conducted to determine the worst
outage incident that can be feasibly
planned for. Examples of incidents to be
studied are:
(1) Lo3: of largest generating unit
within the peninsula of Florida.
(2) Simultaneous loss of the two
largest generating units within the
peninsula of Florida.
(3) Loss of the largest generating
plant in the peninsula of Florida.
It has not been agreed that items (2) or (3)
above should be considered as conditions
which have to be met. The results of this
study will provide a guide in evaluating
the seriousness of such events.
The utilities in Florida are acutely aware of
the need for continuing studies of transiert stability problems, and have implemented procedures for jointly reviewing future transient stability.
1. After the size and location of a new
generating unit has been determined, its
proposed transmission is tested by transient stability studies to examine the
adequacy of the transmission system, and
for the selection of circuit breakers and
protective relaying arrangements. It is
assumed that a three-phase fault will
occur on the most critical line at the
generating station being tested. Stability
is assured for normal relay operation and
also in the event that backup relays
must substitute for the primary relaying,
which increases the fault clearing time.
Problems usually occur when a new
plant is being added, these problems
becoming less severe as additional generation and transmission are added in
the future.
105
T ABLE A-l .-Stabit
SOUTHEA!
Sponsor of Study
Southern
Largest
Unit in
Service
1966
Second
Largest
Unit in
Service
1966
41,400
650
650
Largest
Unit in
Service
1970
Second
Largest
Unit in
Service
1970
Principal Transmission Voltage
in Service 1966
Principal Trans.
mission Volta e
in Service 19 5 0
LEGION
Utilities Co?
Services-Continued
Tennessee Valley Authority
and South Central Electric
Companies.
106
1966
Peak
Load
in MW
:ludics--Continued
1, 150
161-115
500-16
Arkansas Pow{
Central Louisi
Inc.
Empire Distric
Gulf States U1
Kansas Gas &
Louisiana Pov
Mississippi PO
TABLE A-l .-Stabil
SOUTHEAS
Principal Transmission Volta e
in Service 19 7 0
500-161
Studies-Continued
REGION
Utilities Covered by Study
Arkansas Power & Light Co.. .
Central Louisiana Electric Company,
Inc.
Empire District Elec. Co.
Gulf States Utilities Co.
Kansas Gas & Electric Co.
Louisiana Power & Light Co.
Miippi Power & Light Co.
Purpose of Study
Planning the EHV transmission
system for the SCEC-TVA tenyear interchange agreement to exchange 1500 mw of seasonal
power.
Conditions Studied and Conclusions
!. When making transient stability studies,
Southern Services records the transient
currents and voltages as viewed by protective relays on unfaulted lines. This
facilitates determining whether the apparent impedances resulting from those
currents and voltages would cause
opening of circuit .breakers on lines
other than the faulted line and thus
initiate a cascading interruption. In
some instances, studies showed that
usual relay applications and settings
would be susceptible to the currents and
voltages occurring on unfaulted lines
immediately after clearing of the faulted
line. Such studies resulted in relay application and settings to minimize
undesired openings.
3. Where a large portion of the interconnected system must be set up, load
flow studies with phase angle readings
provide a good approximate indication
of stability.
4. The severity of criteria established for
stability of a plant will depend partly
upon whether the system can withstand
the loss of that entire plant without
causing opening of other ties and thus
the “cascade” opening of interconnections. While the loss of an entire plant is
extremely rare, a circuit breaker may
fail to open when tripped by protective
relays, either due to mechanical or
electrical defects, or inability to interrupt the short circuit. Local backup
protection is usually provided to guard
against this condition by opening another breaker, but the plant will then be
exposed to the short circuit for two or
three times the usual clearing interval.
If the fault involves all three phases and
is on a critical line at the plant, then
special expedients may be required to
assure stability. Problems of this type
are being studied in connection with
planned 1969 generating unit additions.
In 1962 a number of load flow studies were
made followed in 1963 by cases run to
investigate transient stability conditions
on the then anticipated 1968 system.
Additional load flow studies and transient
stability cases were run in 1964 through
1966 to update the 1968 system and to
investigate the 1968 conditions.
107
TABLE A-l .-Stabildy
SOUTHEAST
Sponsor of Study
1966
Peak
Load
in MW
Larges
Unit il
Service
1966
Seconc
Lzugea
Unit ir
SeNiCf
1966
Largesl
Unit ir
Service
1970
Largesl
Unit ir
Service
1970
Principal Transmission Voltage
in Service 1966
Principal Transmission Voltage
in Service 1970
.,
REGION
Utilities Cc
Tennessee Valley Authority
and South Central Electric
Companies-Continued
Tennessee Valley Authority
and American Electric Pow
System.
Studies-Continue{
New Orleans Pu
Oklahoma Gas
Public Service C
Southwest Elect]
Tennessee Valle:
Southern Comp:
Illinois Missouri
Missouri-Kansas
Southwestern PC
21,100
6 X
65C
1, 150
1,150
345-161-138
765-500-345
.
Tennessee Valle
American Elect1
500
Virginia Electril
,_
-.,,
:
.
Virginia Electric & Powa
Company.
3,300
570
570
694
570
230-l 15
1
,
CAFWA Pool (CarolinasVirginia).
10,500
570
570
694
650
230-l 15
500-230
VEPCO-AEP-APS-PJM .
10,400
580
570
865
865
345-230-138
765-500-345
108
Virginia Electr
Duke Power Cc
Carolina Powel
South Carolina
Company.
Virginia Elect1
Allegheny Pow
American Elec
Pennsylvania-b
Pool.
LE A-l .-Stability
SOUTHEAST
‘rincipal Transa&ion Voltage
In Service 1970
Studies-Continued
REGION
Utilities Covered by Study
Purpose of Study
New Orleans Public Service Co.
Oklahoma Gas & Electric Co.
Public Service Co. of Oklahoma.
Southwest Electric Power Co.
Tennessee Valley Authority.
Southern Company System.
Illinois Missouri Pool.
Missouri-Kansas Pool.
Southwestern Power Administration.
765-500-345
.
Tennessee Valley Authority.. . . . . . . .
American Electric Power System.
To determine present performance
and the desirability of additiona
EHV extensions.
500
Virginia Electric .& Power Co. .
Planning their 500 kv system. . . .
Virginia Electric & Power Co. . .
Duke Power Company.
Carolina Power & Light Co.
South Carolina Electric & Gas
Company.
Virginia Electric & Power Co . .
Allegheny Power System.
American Electric Power System.
Pennsylvania-New Jersey-Maryland
Pool.
Planning a combined transmission
system which will permit integration of production facilities.
500-230
765-500-345
Preparatory to the development of
3451500 kv transmission facilities
Conditions Studied and Conclusions
These studies were required because of
the addition of very large generators
connected directly to the 500 Kv system
and to determine the timing and location
of interconnections to the system.
A great majority of the cases studied assumed three-phase faults with unsuccessful reclcsing. A few were made
with phase-to-phase or phase-to-ground
faults.
.
These are joint studies in which a greater
part of the Eastern United States is
represented. They are load flow studies
for the 1969-70 conditions but include
various emergency conditions such as
loss of major lines, large generating units
or both. Also cases have been run with
the sudden loss of a plant or large
generating unit, with the lost generation
being picked up by the various systems
proportional to their inert&.
. Stability was investigated for two phaseto-ground faults at several locations on
the 500 kv loop with normal high speed
relaying time and combinations of successful and unsuccessful high speed reclosing. These studies showed that there
was a possibility of instability if high
speed reclosing was used and a permanent
fault existed. This condition is being
corrected by omitting high speed reclosing until a 500 kv tie with Appalachian Power Co. is completed. Either the
500 kv tie to Appalachian Power scheduled for late 1966 or the 500 kv tie with
Allegheny Power scheduled for 1967
would eliminate this problem.
Load flow studies have been made with
the outage of the two largest generating
units on the system. Stability studies will
be made for the years 1968, 1969, 1970
and 1972.
Load flow studies involving major outages
on the EHV system for the years 1968,
1970 and 1972, have been made. Outages
such as loss of all lines on a common
right of way, loss of complete switching
station or loss of all units in a plant were
considered. Stability cases for three phase
faults with normal high speed relaying
and single phase-to-ground faults with
stuck breakers will be studied for cases
that appear critical in load flow
studies.
109
TABLE A-l .-Stability
1966
Peak
Load
ilnMW
Sponsor of Study
Cincinnati-Columbus-Dayton
Group.
-
EAST
-
1zugest
1Unit in
<service
1966
--
second
,argest
Jnit in
krvice
1966
I argest
IJnit in
E iervice
1970
- -
iecond
.argest
Jnit in
iervice
1970
Principal Transmission Voltage
in Service 1966
Principal Transmission Voltage
in Service 1970
cEF$-I’RAL REG:
Utilities Co
9, 700
580
475
800
800
345-138
765-345-138
American Electri
Cincinnati Gas (
Columbus & So1
co.
Dayton Power 8
4 l4,ooo
580
475
865
865
345-138
765-500-345
American Elcctr
Detroit Edison C
Consumers Powc
Northern Indian
Toledo Edison f
Cleveland Elect]
Ohio Edison Co
Penna-New Jers
Niagara Mohavl
Hydro Electric
Ontario.
Power Author?
PJM-APS-VEPCO-AEP
Systems.
30,400
580
570
865
865
345-23w138
765-500-345
American Elect
Allegheny Powe
Penn-New Jersc
Virginia Electri
AEP-CARVA-APS Systems. . .
19,800
580
570
800
800
345-230-138-115
CAPCO (Central Area Power
Coordination Group).
15,900
580
475
800
800
345-138
Michigan-Illinois-Indiana-Ohio
Group.
765-500-345-230
American El&
Allegheny POW{
Carolina Power
South Carolina
Duke Power Cc
Virginia Electr
765-345-138
3
MAIN (Mid-America Interpoc 11
Network).
24,300
580
580 I
715
715
345-l 38
765-345-138
Appalachian P
The Cleveland
co.
Duquesne Ligl
Indiana & Mi
Monongahela
Ohio Edison C
Ohio Power C
Pennsylvania 1
The Potomac
The Toledo E
West Penn Po
American Ela
Commonwcah
Illinois-Missor
Central I1
Illinois Pa
Union Elc
Indiana Powe
Indianapc
Public Se
TABLE A-l .-Stability
EAST
3e
5
Principal Transmission Voltage
in Service 1970
CENTRAL REGION
Utilities Covered by Study
Purpose of Study
765-345-138
American Electric Power Systems.. .
Cincinnati Gas & Elcc. Co.
Columbus & Southern Ohio Electric
co.
Dayton Power & Light Co.
Made necessary by the projection of
generation and 345-Kv transmission.
765-500-345
American Electric Power Systems.. .
Detroit Edison Co.
Consumers Power Co.
Northern Indiana Public Service Co.
Toledo Edison Co.
Cleveland Electric Illuminating Co.
Ohio Ediion Co.
Pcnna-New Jersey-Maryland Pool.
Niagara Mohawk Power Corp.
Hydro Electric Power Comm. of
Ontario.
Power Authority State of New York.
Made necessary by the projected
Michigan 345-Kv interconnections, embracing the entire
Northeast-East Central loop
(Ontario; N.Y., PJM, Michigan
and Ohio-Indiana systems.)
American Electric Power Systems. . .
Allegheny Power System.
Penn-New Jersey-Maryland Pool.
Virginia Electric & Power Co.
Made necessary by development of
large blocks of generation in the
Eastern Ohio-West Virginia Panhandle-Western Pennsylvania
areas.
Preparatory to the development of
their 345/500-Kv transmission
facilities.
765-500-345
765-500-345-230
765-34%138
765-345-138
American Electric Power Systems.. .
Allegheny Power System.
Carolina Power & Light Co.
South Carolina Electric & Gas Co.
Duke Power Company.
Virginia Electric & Power Co.
Appalachian Power Co.. . . .
The Cleveland Electric Illuminating
co.
Duquesne Light Co.
Indiana & Michigan Electric Co.
Monongahela Power Co.
Ohio Edison Co.
Ohio Power co.
Pennsylvania Power Co.
The Potomac Edison Co.
The Toledo Edison Co.
West Penn Power Co.
To determine the effects of the
most severe incidents on the
participants’ systems.
American Elec. Power System.. . . . .
Commonwealth Edison System.
Illids-Missouri Pool:
Central Illinois Public Service.
Illinois Power Co.
Union Electric Co.
Indiana Power Pool:
Indianapolis Power & Light Co.
Public Service Co. of Indiana.
To determine the effects of the most
severe incidents on the participants’
system, embracing an area including Missouri, Iowa, Minnesota,
Wisconsin, Illinois and eastward to
include all of AEP.
Conditions Studied and Conclusions
Extensive load flow and stability studies
are an essential part of planning and
operating procedures. Comprehensive
studies are carried out whenever new
internal or interconnection facilities are
installed or whenever deemed necessary
by changes and additions in facilities
on external systems or by major changes
in system operating conditions and
practices.
Most studies included outages of complete
major power plants and associated transmission, outages of multiple transmission
lines on same right-of-way or transmission
corridor, and outage of major transmission substations or switching stations.
The studies indicated that about half of the
systems would have no system-wide
disruption and no load interruption. As a
result of all the studies, over half of the
systems reported they would have local
load interruption. The loss of load, however, is not the result of instability, but
is simply due to the removal of the source
line or substation. As a result of all of the
studies, one utility reported at least two
severe conditions studied resulted in a
major part of the system being disrupted
with a loss of a major part of the load but
with minor effects on the interconnection.
Also, two systems reported transient instability which resulted in separation of
the system from the interconnection. It
was reported that new interconnections
being constructed and planned will
limit the disturbances to the loss of
certain local loads.
111
-
1966
Peak
Load
iin MW
Sponsor of Study
1Largest
1Unit in
‘service
1966
kcond
,argest
Jnit in
,argest
Jnit in
Service
1970
Second
Largest
Unit in
SeNice
1970
Principal Transmission Voltage
in Service 1966
T ABLE A-l.--Stobili
Stud&-C0ntinufk
EAS
CENTRAL REG
Principal Transmission Volt
in Service 19
“$0
Utilities Cc
--
- -
WiscOnSin Plant
Madison Ga
Wiionsin E
Wisconsin-h
wiinsin P
Wisconsin P
AEP-TVA-Kentucky Systems.
22, ooo
650
650
1, 150
345-161-138
765-500-341
American Elect3
Tcnnessce Valle
Kentucky Utilit
Owcnsboro (Ky
OVEC.....................
16,000
580
475
800
345-138
765-345-X%
American Elect
The Cincinnati
Columbus and
ElectTic co.
Dayton Power
Kentucky Utili
kmiwille Gas i
West Penn Pov
Ohio Edison C
Southern India
The Toledo EC
-
South Cential Electric Companies and Tennessee Valley
Authority.
27,800
-
-
-
-
650
-
650
SOUTH CENTRA
-
1, 150
1, 150
161-l 15
500-16’
REGION
-
Arkansas Pow1
Central Louisi
Empire Distric
Gulf States UI
Kansas Gas &
Louisiana Pov
Mississippi PO
New Orleans
Oklahoma G:
Public Service
Southwestern
Kansas City I
Southwestern
Tenneseeva
LB A-l .--Stabif~
EAST
‘rincipal Transnission Voltage
n Service 1970
Wits-Continued
CENTRAL REGION
Utilities Covered by Study
Purpose of Study
Conditions Studied and Conclusions
Wiinsin Planning Group:
Madison Gas & Electric Co.
Wiionsin Elec. Power Co.
wisconsin-Michigan Power co.
Wiiin Power & Light Co.
Wisconsin Public Service Corp.
765-500-345
American Electric Power System. . . . .
Texmcssee Valley Authority.
Kentucky Utilities Co.
Gwensboro (KY.) Municipal Utilities.
To determine present performance
and the desirability of additional
EHV extensions.
765-345-138
American Electric Power System. . . . .
The Cincirmati Gas & Electric Co.
Columbus and Southern Ohio
F4lectric co.
Dayton Power & Light Co.
Kentucky Utilities Co.
Louisville Gas and Electric Co.
west Penn Power Co.
Ohio Edison Co.
Southern Indiana Gas & Electric Co.
The Toledo Edison Co.
For the initial design to serve the
AEC load and the subsequent AEC
load curtailment.
_.
REGION
500-161
Arkansas Power& Light Co. . . . .
Central Louiiana Electric Co., Inc.
Empire District Electric Co.
Gulf States Utilities Co.
Kansas Gas & Electric Co.
Louiiana Power & Light Co.
Mississippi Power & Light Co.
New Orleans Public Service Co.
Oklahoma Gas & Electric Co.
Public Service Co. of Oklahoma
Southwestern Electric Power Co.
Kansas City Power Co.
Southwestern Power Administration
Temiessee Valley Authority.
To finalize the EHV transmission
system for the SCEC-TVA tenyear interchange agreement to
exchange 1500 Mw of seasonal
power.
EHV line loadings were analyzed from
normal and emergency load flow studies.
System operation was reproduced for
three-phase faults with SCEC breaker
operation to open at six cycles, reclose at
30 cycles and reopen at 36 cycles for
sustained fault conditions. For several
TVA system faults, 4.5 cycle clearing
was used. Special studies were performed
to observe the effects of critical HV line
trip-out following an EHV fault and the
interruption of a large generator prior to
an EHV disturbance.
Studies made in 1961 and 1962 were for
design purposes. Updated studies were
made in 1965 and 1966 to determine safe
operating procedures for the current year
and to observe any critical areas that
may exist in future years.
113
TABLE A-l .-Stabil$
SOUTH CENTRAL
Sponsor of Study
1966
Peak
,oad
IMW
zriz
ervice
1966
econd
arg=t
lnit in
ervice
1966
arg-t
[nit in
ervice
1970
iFEz
ervice
1970
MOKAN Pool. . . . . . . . . . . .
Principal Trammission Voltage
in Service 1970
138
Texas Utilities Company
system.
South Texas Intcrconncctcd
systems.
principal Transmission Voltage
in Service 1966
5, 700
275
27:
565
565
&d&s--Continued
REGION
Utilities Covl
Dallas Power & Li
Texas Power & Li
Texas Electric Ser
138
345-131
Houston Lighti]
Central Power
City Public Ser
San Antonio,
City of Austin 1
Lower Colorad
161-138
345-161-131
Kansas Gas &
Kansas Power
Kansas City PC
Missouri Publi
Empire Distric
Union Electric
Southwestern :
Associated Ele
TABLE A-l .--stab&
SOUTH CENTRAI
Principal Transmission Voltage
in Service 1970
Stud&s-Continued
REGION
Utilities Covered by Study
Purpose of Study
345-13l
Dallas Power& Light Co.. . . . . . .
Texas Power & Light Co.
Texas Electric Service Co.
The companies making up the
Texas Utilities Company system
have been conducting and participating in stability studies for
several years. When major system
changes are contemplated, such as
a new generating unit or plant or
a major transmission addition,
stability studies are made to determine how the addition will
affect the system.
345-138
Houston Lighting & Power Co. . . .
Central Power & Light Co.
City Public Service Board
San Antonio, Texas.
City of Austin Electric Dept.
Lower Colorado River Authority.
The most severe impact possible will
be imposed on each of the individual systems and an analysis
made of the recovery or nonrecovery from these impacts on the
entire interconnected systems.
345-161-138
Kansas Gas & Electric Co.. . . .
Kansas Power & Light Co.
Kansas City Power & Light Co.
Missouri Public Service Co.
Empire District Electric Co.
Union Electric Co.
Southwestern Power Adm.
Associated Electric Coop.
To study the effects of a 345-Kv
transmission line between Wichita,
Topeka and Kansas City scheduled
for service in 1967. The line will be
used initially to transfer 200 Mw
from Wichita to Kansas City.
Conditions Studied and Conclusions
n 1963 this system jointly with Houston
Lighting & Power Company cr-npleted
a stability study to determine the stabilizing effect of a 345-Kv interconnection from Houston to Dallas-Ft. Worth
area. Studies confirmed that the 345-Kv
line would provide a highly reliable
channel for transfer of emergency power
between the areas.
The most recent stability study was for the
1966 peak load conditions and the light
load season of winter 1966-67. Included
among the conditions studied were single
phase-to-ground faults, double line-toground faults, three-phase faults, simultaneous faults on double circuit lines,
single and double bus faults, loss of entire generating plants, and breaker
failure in conjunction with line and bus
faults. Scheduled maintenance and construction schedules were considered in
setting up conditions. Some of these
studies indicated loss of local load, low
voltages in local areas, separation of
areas, but the remainder of the system
was stable.
4 normal steady state load flow and an
emergency steady state load flow have
been completed. The transient stability
studies were to be completed in August.
In these studies the most severe impact
possible will be imposed on each of the
individual systems.
I’ransient stability studies were run in 1964
and 1965 to de&mine the stability of the
systems involved during loss of sections of
the 345-Kv line and/or major generating
units. A series of stability studies are
being run to determine the effect of
prolonged fault condition? in the event a
breaker should fail to operate properly.
It is felt that these conditions represent
the most severe disturbances which might
be encountered in the operation of the
345-Kv line.
Some members of thii group are also members of the South Central Electric Companies and participated in the SCECTVA studies mentioned above.
All transient stability studies which have
been run indicate the systems are stable.
115
TABLE A-l .-Stabili
Studies-Continue?
SOUTH CENTRP
1966
Peak
Load
in MW
Sponsor of Study
Largest
Unit in
Service
1966
Second
Largest
Unit in
Service
1966
358
275
- Missouri Public Service Co.
Largest
Unit in
Service
1970
Second
Largest
Unit in
Service
1970
Principal Transmission Voltage
in Service 1966
161
REGION
Principal Transmission Voltage
in Service 1970
Utilities Cc
345-16!
Missouri Public
Union Electric (
Kansas City PO\
W E S T CENTRA
MAIN. . . . , . . . . . . . . . . . . . . . . !24,300
580
345-138
REGION
765-345-l 3t
I
116
American Elecl
Commonwealtl
Illinois-Missoul
Central Ill.
Illinois Pot
Union Elec
Indiana Powa
Indianapol
Public Ser
Wisconsin Pliu
Madison C
WiiOMh
Wisconsin,
Wisconsin
Wisconsin
A-l .-Stability
‘II CENTRAL
cipal Translion Voltage
iervice 1970
Studies-Continued
I REGION
Utilities Covered by Study
Conditions Studied and Conclusions
Purpose of Study
-Missouri Public Service Co. . . . . . . .
Union Electric Co.
Kansas City Power St Light Co.
T CENTRAL
REGION
765-345-l 38
American Electric Power System. . . .
Commonwealth Edison System.
Illinois-Missouri Pool:
Central Ill. Public Service.
Illinois Power Co.
Union Electric Co.
Indiana Power Pool :
Indianapolis Power & Light Co.
Public Service Co. of Ind.
Wiionsin Planning Group:
Madison Gas & Electric Co.
Wisconsin Electric Power Co.
Wisconsin-Michigan Power Co.
Wisconsin Power & Light Co.
Wisconsin Public Service Corp.
Have under construction a 400 Mw
generating unit and a 345-Kv
interconnection.
1verall performance of the MAIN
grid on a routine and continuing
basis.
The initial study is based on 1968 conditions before Missouri Public Service
Company will have its 345-Kv interconnection. The study will be continued into
1969 when the interconnection is completed. The study will include the loss of
each major unit of the three companies
and numerous transmission line switching
operations. The most severe contingency
to be studied is that all transmission lines
on a common right-of-way will be lost.
This is considered a possibility because of
tornado activity.
A study was completed for 1966 conditions.
Studies are in progress for 1968, 1970, and
1973 conditions.
The 1966 study included investigations of
system integrity for very severe disturbances at various locations throughout the
MAIN system that were considered to be
the most critical from the point of view of
concentrated generation andjor transmission capacity.
In three cases investigated, it was found
that overall integrity of the MAIN system
is maintained and there would be no cascade tripping of transmission lines.
In one case, it was assumed that all four
bus sections at the Meramec station would
somehow be subject to the electrical
equivalent of simultaneous and permanent three-phase faults. This would result
in the loss of all transmission circuits and
872 Mw of generation. The studies of
transient performance for thii case indicated cascade tripping of kansmission
lines to ultimate isolation of the Southern
portion of the Illinois-Missouri Pool,
leaving the area with a capacity deficiency
that would actuate its emergency load
reduction program.
The EHV line under construction will provide increased capacity to the IllinoisMissouri Pool. Under future system conditions this diiturbance at Meramec
should not cause cascade tripping of lines
and service outage would be limited to
loads supplied from Meramec.
TABLE A-l .-Stabilii
-
Sponsor of Study
USBR-MBSG . . . . . . . . . . . .
WEST CENTRAI
-
1966
Peak
Load
IMW
argest
lnit in
ervice
1966
1, 100
200
iecond
.argest
Jnit in
&vice
1966
argest
Jnit in
iervice
1970
econd
,argesl
Jnit in
ervice
1970
Principal Transmission Voltage
in Service 1966
Principal Transmission Voltage
in Service 1970
230-161-115
230-161-11:
Studies-Contin
REGION
Utilities
U.S. Bureau
Missouri Basi
Minnesot
Nebraska
North D;
Coloradc
Iowa
Eastern Wisconsin Utilities. . . .
2,600
310
275
230-l 38
.
MAPP . . . . . . . . . . . . . . . . . . . ,
9, ooa
358
275
:
345-230-131
;
345-231
230
.
;.I
118
!,
m
Wiconsi
Wiconsi
Wionsi
Manitob
Black Hi
Intcrstat
Iowa El{
Iowa-Ill
Iowa Pa
Iowa Pu
Iowa Sa
Lake Su
Minncsc
Montan
Norther
Northwl
otter T
Union 1
cooper:
Dairyla
Eastern
COOP.
Minnkc
Northa
Rural (
17 Mur
TABLE A-l .-Stability
WEST CENTRAL
Insage
P66
Principal Transmission Voltage
in Service 1970
Sn&.r-Continued
REGION
Utilities Covered by Study
-115
230-161-115
U.S. Bureau of Reclamation. . . . . . . . .
Missouri Basin System Group :
15 Municipals.
Minnesota
3 Cooperatives.
3 State InstituNebraska
tions.
3 Municipals.
1 Cooperative.
9 Municipals.
North Dakota
9 Cooperatives.
1 Cooperative.
Colorado
34 Municipals.
Iowa
3 Cooperatives.
9 Cooperatives.
Montana
South Dakota 20 Municipals.
3 Cooperatives.
r138
345-230-l 38
30
345-230
P
t
i
-
Purpose of Study
Conditions Studied and Conclusions
........................
The large geographical area encompassed
by the Federal power system and the
location of several large hydroelectric
plants within the system have made the
problem of system stability under various
loading conditions of particular concern
to the Bureau of Reclamation. Since
January 1964, this group has conducted
or participated in five different system
stability studies. These include investigation of the effects of new interties and
the addition of new generating plants.
Wisconsin Electric Power Co. . .
Wisconsin Power & Light Co.
Wisconsin Public Service Co.
Planning expansion of 345-Kv
transmission in area.
Large-scale stability studies now in progress.
Manitoba Hydro-Electric Board. .
Black Hills Power & Light Co.
Interstate Power Co.
Iowa Elec. Light & Power Co.
Iowa-Illinois Gas & Electric Co.
Iowa Power & Light Co.
Iowa Public Service Co.
Iowa Southern Utilities Co.
Lake Superior District Power Co.
Minnesota Power & Light Co.
Montana-Dakota Utilities Co.
Northern States Power Co.
Northwestern Public Service CO.
Otter Tail Power Co.
Union Electric Co.
Cooperative Power Assn.
Dairyland Power Cooperative.
Eastern Iowa Light & Power
Planning individual segments of
MAPP’s 345-Kv grid.
These studies are unusual in terms of the
area covered but are based on more
normal disturbances as compared to the
MAIN studies.
COOP*
Miiota Power Cooperative.
Northern Minn. Power Assn.
Rural Cooperative Power &an.
17 Municipal Systems.
-
119
287.381 o-67---9
TABLE A-l .-Stability
WEST
Sponsor of Study
1966
Peak
Load
in MW
Second Largest Second
Largest Unit in Largest
Unit in Service Unit in
1966
Service
1970
1966
5%
- - - - - - -
a2
Service
Principal Transmission Voltage
in Service 1966
Principal Transmission Voltage
in Sexvice 1970
Shcdics-Centi
REGION
Utilitie
Pacific Intertie System Technical Studies Task Force.
33,000
495
475
700
700
230 kv
500-230
750 kv dc
Northwest PC
Arizona Pub
salt River PI
California Pc
Los Angeles
PoWa.
USBR, Regi
Western United States Transmission Study Task Force
sponsored by WEST.
45,000
475
475
750
750
230 kv
500-230
750 kv dc
Utilities in tl
-Stability
WEST
Trans‘oltaqe
e 1970
-
Studies-Continued
REGION
Utilities Covered by Study
Conditions Studied and Conclusions
-
cm-230
50 kv dc
Northwest Power Pool. . . . . . . . . . . . .
Arizona Public Service Co.
Salt River Project.
California Power Pool.
Los Angeles Dept. of Water and
Power.
USBR, Region 2 and 3.
00-230
50 kv dc
Utilities in the eleven Western States.
I-
Purpose of Study
For the design of the 500-Kv AC
and 750-Kv DC Pacific intertie.
Comprehensive stability studies are currently being made of the systems associated with the 500-Kv AC and 750-Kv
DC Pacific interties. The studies are
being enlarged to include the entire 2,&Omile Western loop.
Load flow studies are being made of the
transmission network that embraces the
eleven Western states. When the load flow
studies are completed, stability studies
of the same system wilI be made.
The above stability studies will depart
‘from the classical transient type which
uses a first-swing cycle criterion only,
to one that will investigate multiple
swings and include the effects of changing
machine impedances, governor and exciter responses over a period of 15 to 20
seconds or longer if necessary. The
necessity for having this type of study
available was demonstrated when several
long duration power and frequency oscillations (system instability) occurred
after the Pacific Northwest and Pacific
Southwest systems were intercomrected
at Glen Canyon, Arizona in 1!364.
Experience gained in the interconnected
operation of the Western utilities has
shown that unstable conditions with longterm characteristics can develop. Many
studies have been made of these
conditions and installation of damping
devices operating on the governor control
systems has proven that stability can be
achieved by special generator response.
Additional studies are being made of the
resulting system operating conditions and
it is anticipated that system stability can
be considerably improved by using similar
devices to change generator voltage in
relation to frequency changes created by
the unstable conditions.
121
b. Practices for Emergency Load and Generator
Reduction
clined to some predetermined level. More than 11
percent of the systems (20) rely upon the judgment of their system dispatcher to make the correct switching decisions during emergencies.. Thirty
systems do not have any kind of load reduction
program. Of the systems that initiate load shedding
on the basis of a predetermined deviation from normal frequency, 81 do so at or above 59.3 cycles per
second, 31 systems begin their load reduction program between 59.2 and 58.0 cycles per second, and
6 systems initiate action below 58.0 cycles per second. A total of 44 utilities already have or plan
equipment for automatically shedding load at or
above 59.3 cycles per second.
The following tabulations give the responses by
Regions to the survey questionnaires sent out by the
Regional Committees.
Recommendations concerning load shedding and
generator dropping as practices for dealing with
problems of separated systems are discussed in chapter 5 of this report. Other information concerning
load shedding procedures in the area of the United
States affected by the November 9, 1965 power failure is included in chapter 2.
A majority of the electric systems that comprise
the bulk power supply of the United States have
instituted or are in the process of instituting some
type of load reduction program to cope with severe
system disturbances. Nearly 70 percent of the systems responding to inquiries by the Regional Advisory Committee ( 118 out of 175) indicate that
they will shed load when system frequency has de-
I
TABLE A-P.-Ccmparison by region of number of systems using automatic emergency load reduction programs
Total No.
of systems
reporting
Region
Number of users at each frequency step
59.2-59.7 58.6-59.1
cps
cps
Northeast. . . . . . . . . . .
Southeast. . . . . . . . . . . . . . . . . . . . . .
South Central . . . . . . . . . . . . . . . . . . .
West. . . . . . . . . . . . . . . . . . . . . . . . . .
West Central. . . . . . . . . . . . . . . . . . .
East Central. . . . . . . . . . . . . . . . . . . .
33
16
30
34
34
28
0
6
24
1
12
Total. . . . . . . . . . . . . . .
175
44
ll
58.0-58.5
cps
BeloW
58.0 cps
Total No. Total of users’
of users load in percent
of region load
--
0
8
27
8
13
1
1
7
6
7
6
0
0
2
1
18
4
0
57
27
25
1
12
28
29
15
--
10
83
56
94
71
1
11
86
..............
TABLE A-3.-Corn/&son by region of automatic emergency load reduction programs
-
-
Percent automatic load ieduction
Region
-1 &cumulative
59.2-59.7 cps 58.6-59.1 cps 58.0-58.5 cps Below 58.0~ P
I
- -
--
0
Northeast. . . . . . . . . . . . . . . . . . . . . .
Southeast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SouthCentral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
west . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
West Central. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
East Central . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
0
2. 7
14.8
2.8
7. 6
0. 1
5. 3
6. 8
0
3. 7
0. 5
-
total
-
-I
2. 1
3.6
5.9
3. 5
4. 3
0
0
2. 1
0
30. 1
0.2
0
2. 1
13. 7
27.5
36.4
15.8
0.6
G
New York po
Central H
Consolida
Long Isla
New Yorl
Niagara B
Rochester
Power Au
Orange &
Connecticut ’
United 11
Connectic
Hartford
Western 1
Holyoke ’
New Englanc
Boston EC
Cent. Ma
Cent. Vei
Eastern I
Green MN
New Eng
New Eng
PSofNa
Penn.-New J
Public SC
Philadelp
Atlantic 1
Delmarv;
Penna. F
Luzcrne
Baltimore
Potomac
General
Jersey
Metro1
NmJ
Pennsy
CARVA gm
Carolina
Duke PO
S. Caroli
Virginia
see footno
ined level. More than 11
20) rely upon the judg,atcher to make the coruring emergencies.. Thirty
1 kind of load reduction
hat initiate load shedding
nined deviation from nort or above 59.3 cycles per
their load reduction proj.0 cycles per second, and
claw 58.0 cycles per secies already have or plan
ally shedding load at or
nd.
Ins give the responses by
itionnaires sent out by the
iauction programs
TABLE A-4.-Emcrgmcy load reduction flogram
NORTHEAST REGION
59.2-59.7
CP
Group or system
1 4uto
1 matic
NewYorkpowerpool...............
10
83
56
t I
29 15 1
I
94 71 1
I
86 . . . . . . . . . . . . . .
I
E
Below 58.0 cps
0
2. 1
0
30. 1
I
.
0
I
2. 1
13. 7
27. 5
36.4
15.8
0.6
Ud
58.6-59.1
Cps
4uto
natic
CentralHudsonG&E.. . . . . . . . . .
Consolidated Edison I. . . . . . . . . . . .
Lung Island Lighting. . . . . . . . . . . .
NewYorkStateE&G.. . . . . . . . . .
Niagara Mohawk. . . . . . . . . . . . . . . .
Rochester Gas & Elez. . . . . . . . . . . .
Power Auth. State of N.Y . . . . . . . . .
Orange & Reckland Utilities. . . . . .
vaky
.
Elec. Exchange. . .
~MCCtiCUt Light & Power. . . . . . .
Hartford Electric Light . . . . . . . . . . .
Western Massachusetts Electric. . . .
Holyoke Water Power . . . . . . . . . . . .
New England group. . . . . . . . . . . . . . . . .
Boston Edison Co . . . . . . . . . . . . . . . .
Cent. Maine Power. . . . . . . . . . . . . .
Cent. Vermont P.S. . . . . . . . . . . . . .
Eastern Utilities Asscc . . . . . . . . . . . .
Green Mountain Power. . . . . . . . . .
New England Electric . . . . . . . . . . . .
New England Gas & Elec. . . . . . . .
PS of New Hampshire . . . . . . . . . . . .
Penn-New Jemey-Maryland system. . .
Public Serv. Elect. & Gas Co. . . . .
Philadelphia Electric Co . . . . . . . . . .
Atlantic City Electric. . . . . . . . . . . .
Delmarva Power & Light. . . . . . . .
Penna. Power & Light. . . . . . . . . . .
Luaerne Electric. . . . . . . . . . . . . . . . .
Baltimore Gas & Elec . . . . . . . . . . . .
Potomac Electric Power. . . . . . . . . .
General Public Utilities . . . . . . . . . .
Jersey Cent. Power & Light. . . . .
Metropolitan Edison Co . . . . . . . .
New Jersey Power & Light. . . . .
Pennsylvania Electric Co. . . . . . .
.
.
58.0-58.5
cpa
Autc+
Man-
matic
Ud
--
....
10.0
....
15.0
0
0
0
0
. ....
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
. ....
0
0
0
0
0
0
0
0
. ....
0
0
0
0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10. 0
10.0
10. 0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
....
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
....
0
0
0
0
0
0
0
0
....
....
0
....
0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
15.0
0
. .
United Illuminating Co. . . . . . . . . .
1
12
28
dan-
-
--
&MCCtiCUt
Total No. Total of users’
of users load in percent
of region load
Percent load reduction
-
0
0
0
0
0
0
0
0
0
0
0
0
Accumulative
Below 58.0
--
Man-
Auto
1matic
Ud
total
eps
Marl-
hto-
--
Take individual. .
action
. . . do . . . . . . . . . .
. ..do . . . . . . . . . .
. . . do . . . . . . . . . .
. ..do . . . . . . . . . .
. ..do . . . . . . . . . .
. . . do. . . . . . . . . . .
. . . do. . . . . . . . . .
. . . do . . . . . . . . . .
. . . do . . . . . . . . . .
. ..do . . . . . . . . . .
. . . do . . . . . . . . . .
. . . do . . . . . . . . . .
. ..do . . . . . . . . . .
. ..do . . . . . . . . . .
. . . do . . . . . . . . . .
. . . do . . . . . . . . . .
. ..do . . . . . . . . . .
. . . do . . . . . . . . . .
. . . do . . . . . . . . . .
. . . do . . . . . . . . . .
. . . do . . . . . . . . . .
. ..do . . . . . . . . . .
. . . do. . . . . . . .
......
4. 2
0
4. 2
0
4. 2
0
4. 2
0
4. 2
0
4. 2
0
4. 2
4. 2
0
0
4. 2
. . . . .
4. 2
......
4. 2
0
4. 2
......
4. 2
0
4. 2
-
.
....
.
....
. .
. .
....
....
....
....
. . .
....
....
. . .
....
....
....
. . .
. .
....
. .
. . .
....
....
....
....
....
0
0
0
0
0
0
0
0
....
....
0
. . .
0
.
.
.
.
.
.
*
.
.
.
.
.
.
.
.
.
.
. . . . .
5.8
25.0
. . . . .
0
Q
0
0
21.0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
. . ..I
0
0
0
0
(9
0
0
PI
25.0
25.0
25.0
25.0
25.0
25.0
25.0
25.0
25.0
25.0
25.0
25.0
25.0
25. 0
25.0
25. 0
25.0
25.0
25.0
25.0
25.0
25.0
25.0
29.5
29. 5
29. 5
29. 5
29. 5
29. 5
29. 5
29. 5
29. 5
29. 5
29. 5
29. 5
29. 5
29. 5
. . . . .
. . . . .
. . . . .
. . . . .
. . . .
. . . . .
. . . . .
. . . . .
. . . . .
.
.
.
. . . . .
. . . . .
. . . .
.
.
.
.
.
.
. . . .
. . . .
.
. . . . .
. . . . .
. . . . .
&I: i.
25. 3
25. 3
25. 3
25. 3
25. 3
25. 3
25. 3
25. 3
25. 3
25. 3
25. 3
25. 3
25. 3
‘(9;.
;;
(9
-
SOUTHEAST REGION
Lc
CARVA group:
0
21.0/........ 1 0 . . . . . . 27.0
CarolinaPower &Light . . . . . . . . . .
1 . . . . . . / 6.0 . 1 . . . . . 1
Duke Power. . . . . . . . . . . . . . . . . . Has no program.
S.CarolinaElec. &Gas . . . . . . . . . . . Manual shedding as required beginning at 59.0 cps.
. . . . . . 28.5
VirginiaElectric.& Power . . . . . . . . . 1 0 . 2 I . . . . . . 1 1 0 . 1 I . . . . . . 1
8.21........ 1 0
See footnotes at end of table.
Manual
natic
Ud
-
TABLE A-4.-Emergency load rductidn program-Continued
-
SOUTHEAST REGION-Continued
Percent load reduction
-
,, 7 .
59.2-59
Group or system
)
58.6$X1
1
58.r.5
-
.
.
.
.
.
I
A u t o - M a n - A u t o - Mu:- A u t o - Manmatic u a l
matic
matic u a l
--~--5.0
5.0
5.0
5.0
5.0
9.0
..
.
..
..
. . ....
. . ....
. . ....
......
......
......
5 . 0 . . ....
0
........
0
5 . 0 . . ....
0
........
0
5 . 0 . . ....
0
........
0
5.0 . . . . . .
0
........
0
5.0 . . . . . .
0
........
0
Manual as required below 59.2 cps.
Manual reduction as
0
......
0
0
......
0
. . . . . . 30.9
0
0
. . . . . . 16.6
.
Be1ocwps58.0
A~cm~~u$tiv
-I
1
I
- -
Southern Services. . . . . . . . . . . . .
Alabama Power. . . . . . . . . .
Georgia Power. . . . . . . .
Gulf Power. . . . . . . . . . .
Mississippi Power. . . . . . . . . .
Tennessee Valley Authority. . . . .
Florida group :
Florida Power Corp.. . . . .
Florida Power & Light Co. . .
Tampa Electric Co. . . .
Orlando Utilities. . . . . . . .
City of Jacksonville. . . . . . . . .
Others:
Savannah Electric Power. .
S. Carolina Public Service. .
1
required.
......
9.0
......
12.2
......
20.6
......
33.4
blto-
......
......
......
......
......
Manual
..........
..........
..........
..........
..........
As req’d.
......
20.0
......
......
..........
20.0
..........
..........
Manual reduction as required up to 50 percent before 58.0 cps.
I.. . . . :I
2 0 . 0 I.. . . . . . .I 0
I......
0
..........
........
........
........
........
24.0
7.8
0
(4)
-
EAST CENTRAL REGION
American Electric Power:
Appalachian Power. . . . . . . . . . . . .
Indiana & Michigan. . . . . . . . . . . . .
Kentucky Power. . . . . . . . . . . . . . . .
Kingsport Power. . . . . . . . . . . . . . .
Ohio Power. . . . . . . . . . . . . . . . . . . .
Wheeling Electric.. . . . . . . . . . . . . .
Allegheny power system :
Monongahela Power. . . . . . . . . . . . .
Potomac Ediion. . . . . . . . . . . . . . . . .
West Penn Power. . . . . . . . . . . . . . . .
Ohio-Pennsylvania:
Cincinnati Gas & Elec. . . . . . . . . . .
Cleveland Elec. Illum s . . . . . . . . . . .
Columbus & Southern Ohio Elec .
Duquesne Light Co. . . . . . . . . . . . . .
Ohio Edison Co. . . . . . . . . . . . . . . . .
Toledo Edison Co. . . . . . . . . . . . . . .
Indiana group:
Indianapolis Power & Light. .
Pub. Serv. Co. of Indiana. . . . .
Southern Indiana Gas & Elcc.
Northern Indiana Pub. S,erv. .
See footnotes at end of table.
\r
rhe vast number and wide distribution of interconnections on the AEP system, its
distribution of reasonably sized generating plants relative to its size of system and
its continued adherence to a program of transmission development makes the
general application of load shedding thus far impracticable and unnecessary on the
AEP system. Interruptible lqads play an important role in maintaining the integrity of AEP’s generation. These loads presently amount to 5.40/, of the system
total.
. 1Drop 24 Mw ( 1 .O percent) interruptible load by manual means at 59.9 cps. Manual
reduction of selected customer load at 59.5, 59.0, 58.5, and 58.0 cps. Power
:I stations to take independent action to save the station at 57.5 cps.
1
I
t
x 1 :;:x j 8 1 Go I x
0
0
Manual load reduction as required.
0 0
20.0
0 110.0 1 0 1 10.0 1 0
0
0
Manual reduction as required.
j percent load relief via 5 percent voltage reduction and 1 percent load reduction
by shutting down interruptible customers if disturbance is not severe. For more
severe conditions, up to 50 percent manual load reduction in 19 steps.
:
zi
...
. .
50.0
20.0
/
;;g
/
H
/
:;i:
/
ij
/
Shed load as required below 58.5 cps. 24.0
1;o 1 8 / 8 / ; I
g; ~
.......................................................................
Kentucky g
East Kc
Kentuc
Ownest
Louisvi
OVEC
Michigan g
Consun
Detroit
Detroit
Lansinl
South Cen
Middle
.t
LO
Mi
NC
Kansar
Centri
Empir
Gulf S
Oklah
Pub. ,c
South?
Southwest
west ’
Kansa
Kansa
Kansz
St. Jo
City c
Weste
Misso
Spring
Dentc
Brow]
south Te
Hous
Centx
City (
City (
Lowe
See foo
124
TALL& A-l.-Emergency load reduction program--Continued
EAST CENTRAL KEGION-Continued
I
w 58.0
w
ManUd
Accumulative
total
Automatic
Group or system
..........
..........
..........
..........
..........
. . . . . .
. . . . . .
. . . . . .
. . . . . .
4s req’d.
. . . . . .
20. 0
..... .
......
59.2-59.7
cps
58.6-59.1
cps
58.0-58.5
cps
Auto- Man- Auto- Manmatic u a l matic u a l
-
Manual
-. . . . .
Percent load reduction
Below 58.0
cps
Automatic
Kentucky group:
13.5
0
5.6
East Kentucky REA.. . . . . . . . . . . . . .
0
13.5
0
Kentucky Utilities Co. . . . . . . . .
0
5.6
13.5
0
Ownesboro Municipal. . . . . . . . .
0
5.6
LouisvilleGas&Elec.. . . . . . . . . . . .
Manual load reduction as required.
OVEC . . . . . . . . . . . . . . . . . . . . . . . . . . I
Michigan group :
Consumers Power Co. . . . . . . . . . . . .
DetroitEdisonCo.. . . . . . . . . . . . . . .
Manual load reduction as required.
Detroit Public Lighting. . . . . . . . . . . .
Lansing Water & Light. . . . . . . . . . . . I
4utomatic
Accumulative
total
4utonatic
Manual
2.8
2.8
2.8
SOUTH CENTRAL REGION
ons on the AEP system, its
ive to its size of system and
u1 development makes the
able and unnecessary on the
ole in maintaining the inBunt to 5.4’?$ of the system
means at 59.9 cps. Manual
8.5, and 58.0 cps. Power
at 57.5 cps.
‘0
0
0
0
50.0
20.0
0
0
20.0
F
\ 1 percent load reduction
x is not severe. For more
ion in 19 steps.
Aired below 58.5 cps. 24. 0
30.0
20.0
......................
South Central group s. . . . . . . . . . . . . . . .
Middle South Utilities . . . . . . . . . . . . .
Arkansas Power & Lights . . . . .
Louisiana Power & Light s. . . .
Mississippi Power & Light s. . . .
New Orleans Public Service s . . .
Kansas Gas & Electric s . . . . . . . . . . .
Central Louisiana s. . . . . . . . . . . . . . .
Empire District s. . . . . . . . . . . . . . . . .
Gulf States Utilities s . . . . . . . . . . . . . .
Oklahoma Gas & Electric s . . . . . . . .
Pub. Serv. Co. of Oklahoma. . . . . . .
Southwest Electric Power C0.s. . . . .
Southwest group :
West Texas Utilities s. . . . . . . . . . . . .
Kansas Power & Light 6. . . . . . . . . . .
Kansas City Power & Light 6. . . . . . .
Kansas City Municipal 7 . . . . . . . . . . .
St. Joseph Light & Power 7. . . . . . . . .
City of Independence 6. . . . . . . . . . . .
Western Farmers Coop.6 . . . . . . . . . . .
Missouri Public Service Co.6. . . . . . .
Springfield, Missouri. . . . . . . . . . . . . .
Denton, Texas. . . . . . . . . . . . . . . . . . .
Brownsville Municipal. . . . . . . . . . . . .
South Texas system. . . . . . . . . . . . . . . . . .
Houston Light & Power Co. . . . . . .
Central Power & Light Co. . . . . . . .
City of San Antonio. . . . . . . . . . . . . .
City of Austin. . . . . . . . . . . . . . . . . .
Lower Colorado River. . . . . . . . . . .
See footnotes at end of table.
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10.0
10. 0
. . . . 20.0
.....
.
.
. . .
.
20.0
20.0
20.0
20.0
20.0
.
20.0
20.0
. . . 20.0
20.0
.
.
20.0
20.0
.
20. 0
....
. .
. . .
. . .
.
....
. . .
. . .
. . .
.
. .
.
.
6.0
4.0 .
. . . 20. 0
10.0
.
. . . 20.0
10.0
....
. . . 20.0
10.0
.
.
. . . 20.0
10.0
.
10.0
. .
20.0
.
. 20. 0
10.0
.
. 20.0
. .
10.0
10.0% automatic at unspecified frequency (future).
Manual shedding of up to 100 percent load in 8 steps.
Manual reduction as reouired when frequency drops to 59.5 c
......
25.6
5.0
......
5.0
25.0
......
5.0
25.0
5.0
......
25.0
5.0
......
25.0
5.0
......
25.0
.........
.........
.........
.........
.........
.........
125
TABLE A-4.-Emergency load reduction flogram--Continued
SOUTH CENTRAL REGION-Continued
Percent load reduction
59.2-59.7
Group or system
58.6-59.1
58.0-58.5
Below 58.0
Accumulative
total
GX
Auto- Manual
matic
Texas Utilities system:
Dallas Power & Light Co. . . . . . .
Texas Power & Light Co. . . . . . .
Texas Electric Service. . . . . . . . . .
Manual operations according to a definite plan augmented by under frequency
relays and interruptible industrial load. The Ft. Worth-Dallas area load can be
reduced by use of supervisory control. Load would be reduced in whatever amounts
necessary to maintain system frequency at or above 58 cps. In one large area of the
system which is subject to isolation, under frequency relays are set to disconnect
30 percent of the area load at 59 cps. The largest single manually interruptible load
is 60,000 Kw.
WEST CENTRAL REGION
Wisconsin group:
Wisconsin Public Serv. . . .
Wisconsin Power & Light. .
Wisconsin Electric Power. .
Wisconsin-Michigan Power.
Madison Gas & Electric. . .
Upper Pennisula Power. . . .
Edison Sault Electric.. . . . .
Commonwealth Edison Co..
Illinois-Missouri pool. . . . .
Union Electric Co. . .
Cent. Illinois Pub. Serv. . .
Illinois Power Co. . .
Central Illinois Light.. . . . .
Iowa pool.. . . . . . .
Iowa-Electric L & P. .
Iowa-Illinois G & E . . .
Iowa Public Service.. . . . . .
Iowa Southern Util.. . . . .
Iowa Power & Light. .
Corn Belt Power Coop. .
Nebraska Public Power Sys.. .
Omaha Public Power District. . .
Missouri Basin Systems Group..
.
..
.
.
Upper Mississippi Valley power pool:
Cooperative Power Assoc. . . . .
Dairyland Power Coop. . .
Interstate Power Co.. . . .
Lake Superior District.. .
Minnesota Power & Light . . .
Minnkota Power Coop. . . .
Montana Dakota Utilities.. . .
Northern Minn. Power Assoc.
Northern States Power Co. . .
Northwestern Public Service.
Otter Tail Power Co. . . . . .
Rural Cooperative Power. . . .
United Power Assoc.. . . . . .
See footnotes at end of table.
126
0
19.0
0
19.0
r)
0
0
0
0
0
0
20.0
0
5.0
0
5.0
0
10.0
0
0
0
5.0
0
10.0
0
30.0
15.0
0
0
0
0
0
0
0
0
0
0
0
0
0
10.8
0
0
0
5.4
0
5.4
0
21.6
0
0
1 1 . 2 3 4 . 0 27.6
0 ’
0
0
0
16.4
34.0
Manual load reduction as required.
45.0
15.0 . . . . . .
0
7. 0 30. 0
7.0 . . . . ‘..
20. 0
6.0
42.0
0 . 2 4 2 . 0 24.0
10. 7 . . . . . . . .
0 . 6 . . . . . 12.5 . . . . . .
42.0
0 . 2 4 2 . 0 24.0
0 . 6 . . . . . . 12.5 . . . . . .
10. 7 . . . . . . . .
42.0
0. 2 4 2 . 0 24.0
0 . 6 . . . . . . 12.5 . . . . . .
10. 7 . . . . . . . .
0 . 2 4 2 . 0 24.0
42.0
0 . 6 . . . . . . 12.5
. . .
10.7 . . . . . . . .
Manual reduction as required up to 8 percent of system.
10.0 . . . . . . 20.0 . . . . . .
0
.._.......
........
0
.....
10.0 . . . . . . 2 0 . 0 . . . . . .
0
0
..........
........
.....
10.0 . . . . . . 20.0 . . . . . .
........
0
.....
0
. .........
10.0 . . . . . . 20.0 . . . . . .
0
.._.......
........
0
.....
10.0 . . . . . . 20.0 . . . . . .
0
. .........
........
0
.....
........
0
.....
10.0 . . . . . . 2 0 . 0 . . . . . .
0
. .........
10.0 . . . . . . 20.0 . . . . . .
0
. .........
.......
0
.....
.......
10.0 . . . . . . 20.0
.
.
0
..........
0
.....
10.0 . . . . 2 0 . 0 . . . . . .
0
........
0
.....
. .........
Wider operating range of hydrogeneration eliminates the need for a load reduction
program.
IO percent initial automatic reduction supplemented by manual as required before
decay to 58.0 cps.
0
......
6.6
.
.
.
13.4 . . . . . . . . . . . . . . 25.0
20.0
25.0
10 percent initial automatic reduction supplemented by manual as required before
d-[tos-[vs.
1
1
1
1
(
(
1
c
Northwest pow
So. IdahoIdaho
USBR
Utah-E. Ic
UtahI
Central & ‘
Monta
Bonnel
E. Wash.-?
Washir
Bonnet
west E
Central W:
Washir
Bonnet
Pacific
Puget !
Chelan
Grant 1
Puget Sour
British
Seattle,
Bonnet
Puget !
Tacom
Southern C
Pacific
Portland-M
Portlan
Bonna
Pacific
Eugene
Rocky Mounta
AreaI....
Mental
Bonna
Arcas II, I
Mental
USBR
Area III, I
Utah &
Bonnev
Prefere
Califor
Area IV..
Pacific
Tri St;
USBR
See footnotes
TABLE A-4.-Emergency load rcduckon program-Continued
WEST REGION
Percent load reduction
-
-
Itive
59.2-59.7
cps
Group or system
ml al
Auto- Man..
matic
Ud
-xn be
IlOUIltS
I
of the
le load
19.0
20.0
30.0
0
21.6
V34.0
45.0
42.0
42.0
42.0
42.0
.....
.....
. . . .
. . .
. . . .
,....
.....
,....
action
CfOrC
25 .O
--
I
1
1
1
1
Northwest power pool. . . . . . . . . . . .
So. Idaho-E. Oregon . . . . . . . . . . . . .
Idaho Power Co. . . . . . . . . . . . .
USBR . . . . . . . . . . . . . . . . . . . . . .
Utah-E.Idaho . . . . . . . . . . . . . . . . . .
UtahPower&LightCo . . . . . .
Central & W. Montana . . . . . . . . . . .
Montana Power Co. . . . . . . . . .
Bonneville Power Adm. . . . . . . .
E. Wash.-N. Idaho-W. Kootenay.
Washington Water Power Co. .
Bonneville Power Adm . . . . . . . .
West Kootenay Pr. & Lt. Ltd.
Central Wash.-Oregon . . . . . . . . . . .
Washington Water Power Co. .
Bonneville Power Adm . . . . . . . .
Pacific Power & Light . . . . . . . . .
Puget Sound Power & Lt. Co. .
Chelan County P.U D . . . . . . . .
Grant County P.U.D. . . . . . . . .
Puget Sound-SW British Columbia.
British Columbia Hydro . . . . . . .
Seattle, Dept. of Lighting. . . . .
Bonneville Power Adm . . . . . . . .
Puget Sound Power & Lt. Co. .
Tacoma, Dept. of Pub. Util.
SouthernOregon . . . . . . . . . . . . . . . . .
Pacific Power& Light Co . . . . . .
Portland-Willamette-Oregon Coast.
Portland General Electric. . . . . .
Bonneville Power Adm. . . . . . . . .
Pacific Power & Light Co. . . . . .
Eugene Water & Elec. Bd. . . . .
Rocky Mountain power pool.
Area1 . . . . . . . . . . . . . . . . . . . . .
Montana Power Co. . . . .
Bonneville Power Adm. . .
Areas I I , I I - A , I I - B .
Montana Power Co. .
USBR Reg. 6. . . . . ,
Area III, III-A.. . . . , .
Utah & Idaho . . .
Bonneville Power Adm.
Preference Customers. . . . . .
California Pacific Util. Co..
Area IV.. . . . . . . . . . . . . . . . . .
Pacific Power & Light Co.
Tri StateG&TAssoc.....
USBR Reg. 4. . . . . . . . .
See footnotes at end of table.
_0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
58.6-59.1
cps
-. . . .
.
.
.
.
.
. . . .
. . .
. . . .
. . .
.
. . .
.
.
. . .
. . . .
. . .
.
.
.
.
.
.
.
.
. . .
.
.
.
.
.
.
.
. . .
. . .
.
.
.
.
.
.
.
.
.
.
.
.
.
. . .
.
.
.
.
.
.
.
.
.
.
. . .
. . . .
. . .
.
. . .
.
.
. . .
J
--
,Auto1matic
3. 8
22. 6
24. 4
0
14. 7
14. 7
8. 7
13. 3
0
3. 2
0
0
11.4
1. 1
0
0
4. 6
0
0
0
2. 3
0
0
11. 8
0
0
0
0
0. 9
0. 3
0
3. 5
0
9. 4
7. 0
15.0
0
12.0
13.0
0
25. 0
35. 0
0
0
0
8. 0
12.0
0
0
--
Mall-
58.0-58.5
cps
Automatic
Ud
-. . .
. . . .
. . . .
.
.
. . . .
. . .
.....
.....
. . . .
.....
.....
. . . .
. . . .
. . . .
.....
.....
.....
. . . .
. . . .
.
. . . .
. . .
.
.....
.....
.
.
.
.
.
.
.
.
.
.
.
.
.
. . . .
. . .
. . . .
.
.
.
.
.
. . .
. . .
.....
.....
. . .
. . .
.....
.
.
. . . .
MarlUd
-1. 5
2. 3
2.4
0
12. 3
12. 3
1. 3
2. 0
0
1.8
0
0
6. 3
0
0
0
0
0
0
0
1. 0
0
0
4. 9
0
0
0
0
0. 5
0
0
2. 1
0
16. 7
41.0
15.0
68.0
47. 0
48.0
0
6. 5
9. 2
0
0
0
16.0
24. 0
0
0
--
Below 58.0
cps
-
I
Accumulative
total
.-
Auto . 1Man- Auto.
/ matic
matic
Ud
-- --_
....... 30. 3
...... 10. 1
...... 10. 9
......
0
...... 22. 4
...... 22. 4
...... 2 7 . 0
......
2. 8
...... 72. 9
...... 42. 8
...... 49. 2
...... 73. 6
...... . . . . . .
...... 22. 5
...... . 1 00.
...... 28. 9
......
4.6
...... . 1 00.
......
0
......
0
...... 39. 5
...... 27. 9
...... 64. 0
......
7. 2
...... 72. 3
...... 22. 8
...... 63. 2
...... 63. 2
...... 17. 3
......
6. 3
...... 35. 0
8. 5
......
...... 55.0
......
4. 3
......
8.0
0
......
...... 16. 0
......
0
......
0
......
0
...... 13. 5
...... 19. 1
......
0
......
0
......
0
...... 15.0
...... 2 1 . 0
......
0
......
0
16.4 35. 1
2. 5 35.0
. . . . 37. 7
34. 6
0
. . . 49. 4
. . . 49. 4
. . . . 37. 0
. . . . 18. 1
.
. 72. 9
11.4 47. 8
15.0 49. 2
12. 9 73. 6
4. 5
17. 7
18. 6 23.6
.
.1 00.
16. 2 28. 9
30. 7
9. 2
. . . . 1 00.
0
0
0
0
6. 5 42. 8
. . . . 27. 9
. . . 64.0
30. 2 23. 9
72. 3
3.6
. . 22.8
‘4.6 63. 2
4. 6 63. 2
43. 7
18. 7
48. 3
6. 6
44.7 35. 0
14. 1
31.4
. , . . 55.0
. . . . . 30.4
. . . . . 56. 0
. . . . . 30. 0
. . . . . 84. 0
. . . . . 59.0
. . . . 61.0
. . . .
0
. . . . 45.0
. . . . . 63. 3
. . .
0
0
.....
. . .
0
. . . . . 39.0
. . . . . 57. 0
. . . .
0
0
.....
16.4
2. 5
.........
34. 6
.........
.........
.........
.........
.........
11.4
15. 0
12. 9
4. 5
18.6
.........
16. 2
30. 7
.........
0
0
6. 5
.........
.........
30. 2
3. 6
.........
4. 6
4. 6
43. 7
48. 3
44.7
31.4
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
127
TABLE A-4.-Emergency load reduction program-Continued
WEST REGION-Continued
Percent load reduction
-
Group or system
59.2-59.7
cps
b-----l-
Rocky Mountain power pool-Con.
Areav. . . . . . . . . . . . . . . . . . . . . . . . . .
0
......
0
.....
Pacific Power & Light Co . . . . . . .
TriStateG&TAssoc.. . . . . . . .
0
.....
0
.....
Cheyenne Lt., Heat & Pr. Co. .
Consumers PPD . . . . . . . . . . . . . . .
0
.....
AreaVI . . . . . . . . . . . . . . . . . . . . . . . . .
0
.....
USBR Reg. 4 . . . . . . . . . . . . . . . . .
0
.....
0
.....
Western Colorado Pcwer Co. . .
Colorado-Ute Elec. Assoc. . . . . .
0
.....
0
AreaVII . . . . . . . . . . . . . . . . . . . . . . . .
.....
Public Service Co. of Colorado.
0
.....
So. Colorado Power Div . . . . . . . .
Colorado Springs Pub. Util. . . . .
0
.....
0
USBRReg.7.. . . . . . . . . . . . . . . .
.....
TriStateG&TAssoc.. . . . . . .
0
.: . . .
REA,G&T’s,Munic.. . . . . . . .
0
.....
California-Nevada group:
Sacramento Muni. Util. Dist . . . . . . . . . . . . . . . . . .
Sierra Pacific Power Co. . . . . . . . . . . Equipment
Pacific Gas & Electric Co. . . . . . . . . . . . . . . . . . . . .
Southern California Edison Co. . . . . . . . . . . . . . . .
LosAngelesDept.ofWater&Power. . . . . . . . . . . .
SanDiegoGas&ElectricCo.. . . . . . . . . . . . . . . . .
Arizona-Nevada group :
Arizona Public Service Co. . . . . . . . . . . . . . . . . . . .
Arizona Power Authority. . . . . . . . . . . . . . . . . . . . .
ArizonaElectricCoop . . . . . . . . . . . . . . . . . . . . . . . .
USBRReg.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Nevada Power Co. . . . . . . . . . . . . . . . . . . . . . . . . . .
Salt River Project. . . . . . . . . . . . . . . . . . . . . . . . . . .
Tucson Gas & ElectricCo . . . . . . . . . . . . . . . . . . . .
New Mexico-Texas group:
USBRReg.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Plains Electric G & T Coop. . . . . . . 10.0 . . . . .
Community Public Service . . . . . . . . . . . . . . . . . . . .
Public Service Co. of New Mexico. . . . . . . . . . . . .
El Paso Electric Co. . . . . . . . . . . . . . . . . . . . . . . . . .
58.6-59.1
cps
--
Auto- Man.*
matic u a l
.-
58.0-58.5
W
Below 58.0
cps
Accumulative
total
-_
/Auto- Man1matic u a l
A u t o - M a n - A u t o - M a nI- Automatic
matic u a l
Ud
matic
-.-~~-- - -
Manual
1.0 . . . . . . . .
0
.....
5.0 . . . . . .
6.0
0
. . . . . .
0
13.0 . . . . . .
. . .
13.0
0
. . . .
0
0
......
. . . .
0
f.....
0
0
0
0
0
......
8.0
::::::::
0
:::::
a. 0
0
......
. . . . . .
0
0
0
0
0
......
0
. . . . .
0
0
0
0
......
0
.......
0
0
0
0
......
0
0
0
0
20.0 : : : : : : : : 10.0 . . . . .
0
......
30.0
......
0
30.0 . . . . . . . . 23.0 . . . . .
53.0
Equipment on order (Frequency not specif ied )
. . . . . .
0
1. . . . . .
0
0
. .
0
. . . . . .
0
.......
. . .
0
0
0
0
.......
0
. .
0
0
I. . . . . . I
0
. . . . . .
0
.......
0
0
. .
.........
.........
.........
.........
.........
0
0
0
0
.........
.........
-- -
New York POT
Central H
Consolida
Long Islai
New York
.........
.........
.........
.........
,
.
.
I
I
. I...... I . . . . . . I . . . . . .
L order (frequency not specified)
I
I
I
.
.....
. . .
YeJ
.........
.....
. . .
.....
* . .
. . .
....
.
. .
29.0
36.0
40.0
27.0
.........
.........
.........
.........
. . . .
.
. . .
.
.
.
. . . .
. . .
...........................
....................
...............
.....
...............
.....
. . .
....................
...............
.....
....................
t Has an automatic load relief program wherein voltage is automatically reduced by underfrequency relays,
5% at 59cps to provide a 2.3% load reduction and 3Cr, at
58.5 cps to provide an additional 1.570 load relief.
*Have equipment orders in process to bring automatic
load shedding to approximately 30 percent.
3 300/, of load will be under automatic control by end of
1968.
4 Additional reduction can be accomplished by super-
128
-7
.........
. .........
YeS . . . . . . . . .
67. 0 . . . . . . . . .
30.0 . . . . . . . . .
61.0 . . . . . . . . .
YeS . . . . . . . . .
. . .
. . .
........
ii’
,’ . . . . . . . . .
YeS
........
YeS . . . . . . . . .
........
Yt3
. . .
0
.
.
. .
-
Green M
New Eng
New En8
Public SC
Pennsylvania
38.0
. .
.
.
.
.
Niagara 1
Orange &
Rochester
Power Au
Connecticut 7
United 11
Connectic
Hartford
Western 1
Holyoke ’
New Englanc
Boston EI
Central n
Central \
Eastern I
.
-
-
visory control. Transfer tripping of 148 Mw (24 percent
is planned for loss of City’s largest unit (250 Mw).
5 Program not yet in effect but scheduled for 1967 corn
pletion.
s 20 percent more is planned in steps at 59.3, 59.0 ant
58.7 cps.
7 Program not yet in effect but scheduled for 1968
pletion.
corn
CARVA Grc
Carolina
Duke PC
s. Carol
Virginia
Florida Grow
Florida
Florida
Tampa
Orlandc
City of.
Southern St
Tennessee 7
Savannah E
S. Carolina
See footnc
TABLE A-5.--Load aad gmrabon emergency dropping pm&es
NORTHEAST REGION
Open Interconnections
on Low Frequency
Group or System
-
-
Manual
........
........
........
........
........
0
0
0
0
........
........
.......
/.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
.......
lercent)
17 com9.0 and
i8 com-
-_
l-
ulative
:al
Drop Generation on Loss
of Load
New York Power Pool. . . . . . . . . . . . . . . . .
Central Hudson Gas & Electric. . . .
Consolidated Edison . . . . . . . . . . . . . . . . .
Long Island Lighting. . . . . . . . . . . . . . . .
New York State Elec. & Gas . . . . . . . . . .
Niagara Mohawk. . . . . . . . . . . . . . . . . . .
Orange & Rockland. . . . . . . . . . . . . . . . .
Rochester Gas & Electric. . . . . . . . . . . . .
Power Authority, State of New York. ..
Connecticut Valley Electric Exchange . . . . .
United Illum. Co. . . . . . . . . . . . . . . . . . .
Connecticut Light & Power. . . . . . . . . . .
Hartford Electric Light. . . . . . . . . . . . . .
Western Massachusetts Elect . . . . . . . . . .
Holyoke Water Power. . . . . . . . . . . . . . .
New England Group . . . . . . . . . . . . . . . . . . . .
Boston Edison Co. . . . . . . . . . . . . . . . . . .
Central Maine Power. . . . . . . . . . . . . . . .
Central Vermont Public Service . . . . . . .
Eastern Utilities Assoc. . . . . . . . . . . . . . .
Green Mountain Power . . . . . . . . . . . . . .
New England Electric. . . . . . . . . . . . . . .
New England Gas & Electric. . . . . . . . .
Public Service of New Hampshire. . . . .
Pennsylvania-New Jersey-Maryland. . . . . . .
Not planned but as a last
resort.
. . . . . do . . . . . . . . . . . . . . . .
. . . . . do . . . . . . . . . . . . . . . .
. . . . . do . . . . . . . . . . . . . . . .
. . . . . do . . . . . . . . . . . . . . . .
. . . ..do . . . . . . . . . . . . . . . .
. . . . . do . . . . . . . . . . . . . . . .
. . . . . do . . . . . . . . . . . . . . . .
. . . . . do . . . . . . . . . . . . . . . .
. . . . . do . . . . . . . . . . . . . . . .
. . . . do. . . . . . . . . . . . . . . .
. . . . do . . . . . . . . . . . . . . . .
. . . . . do . . . . . . . . . . . . . . . .
. . . . do . . . . . . . . . . . . . . . .
. . . . do . . . . . . . . . . . . . . . .
. . . . do . . . . . . . . . . . . . . . .
. . . . do . . . . . . . . . . . . . . . .
. . ..do . . . . . . . . . . . . . . . .
. . . . do . . . . . . . . . . . . . . . .
. . . . do . . . . . . . . . . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
. . . . do . . . . . . . . . . . . . . . .
. . . . do . . . . . . . . . . . . . . . .
. . . . do . . . . . . . . . . . . . . . .
. . ..do . . . . . . . . . . . . . . . .
Openat59.0cps.. . . . . .
......................
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
(1). . . . . . . . . . . . . . . . . . . .
.
0.
0.
Once in 15 yrs.
2.
1.
1 manual.
0.
0.
ii0............. .........................
1.
1.
1.
1.
0.
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
.......................
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
Automatically on 10%
ovelspeed.
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
(2). . . . . . . . . . . . . . . . . . . . .
CARVA Group:
Carolina Power & Light . . . . . . . . . . . . .
Duke Power . . . . . . . . . . . . . . . . . . . . . . . .
S. Carolina Electric & Gas . . . . . . . . . . .
Virginia Electric & Power. . . . . . . . . . .
Florida Group :
Florida Power Corp. . . . . . . . . . . . . . . . .
Florida Power & Light. . . . . . . . . . . . . .
Tampa Electric Co . . . . . . . . . . . . . . . . . .
Orlando Utilities . . . . . . . . . . . . . . . . . . . .
City of Jacksonville. . . . . . . . . . . . . . . . .
Southern Services. . . . . . . . . . . . . . . . . . . . . .
Tennessee Valley Authority . . . . . . . . . . . . . .
Savannah Electric & Power. . . . . . . . . . . . .
S. Carolina Public Services . . . . . . . . . . . . . .
See footnotes at end of table.
.
.
0.
0.
0.
0.
1.
1.
0.
0.
0.
-
-
-
No. of Occasions
Load Shedding Used
in 1965
SOUTHEAST REGION
No policy . . . . . . . . . . . . . . .
. . . do. . . . . . . . . . . . . . . . . .
. . . do. . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . .
No policy . . . . . . . . . .
No. . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . .
Open at 58.3 cps. . .
Yes. . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
0.
0.
0.
0.
No. . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
Separate Indian River
Plant #l with 60 Mw.
Load at 58.0 cps.
. . . No . . . . . . . . . . . . . . . . . . . .
. . . No. . . . . . . . . . . . . . . . . . . .
. . . No . . . . . . . . . . . . . . . . . . . .
...........................
...........................
0.
0.
0.
0.
...
...
...
...
0.
0.
0.
0.
0.
TABLE A-5.--Load and generation emergemy dra#ing practices--Continued
SOUTHEAST REGION-Continued
Group or System
CAPCO Group:
American Electric Power . . . . . . . . . . . . . .
Allegheny Power System. . . . . . . . . . . . . .
Cincinnati Gas & Electric. . . . . . . . . . . .
Cleveland Electric Illum. . . . . . . . . . . . . .
Coldmbus & So. Ohio Elec. . . . . . . . . . .
Duquesne Light Co. . . . . . . . . .
OhioEdiinCo . . . . . . . . . . . . . . .
Toledo Edison Co. . . . . . . .
Indiana Group :
Indianapolis Power & Light.. . . .
Public Service Co. of India. . .
Southern Indiana Gas & Elec .
Northern Indiana Public Serv. . .
Kentucky Group :
East Kentucky REA.. . . . . . . . .
Kentucky Utilities Co. . . . . .
Owensboro Municipal. . . . . . .
Louisville Gas & Electric. . . . . .
Michigan Group :
ConsumersPowerCo . . . . . . . . . .
Detroit Edison Co. . . . . . . .
Detroit Public Lighting. . . . .
Lansing Water & Light. . . . . .
. .
...
. .
...
. .
.
. . .
Open Interconnections
on Low Frequency
Drop Generation on Loss
of Load
No. of Occasions
Load Sheddirig Used
in 1965
No. . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
Openat 58.2 cps . . . . . . . .
Open 58.0 cps. . . . . . . . . . .
Now being engineered
for automatic operation.
Openat58.5cps.. . . . . . .
Openat59.0cps.. . . . . . .
. . . do . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
0.
0.
0.
0.
0.
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
1.
0.
0.
Openat58.0cps.. . . . . . .
Openat57.5cps.. . . . . . .
Openat58.0cps.. . . . . . .
.......................
No . . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
0.
0.
0.
0.
Openat57.5cps.. . . . . . . No . . . . . . . . . . . . . . . . . . . .
. . . do . . . . . . . . . . . . . . . . . . No . . . . . . . . . . . . . . . . . . . .
. . . do . . . . . . . . . . . . . . . . . . No . . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . .
Openat58.0cps . . . . . . .
Openat58.5cps . . . . . . . .
. . . do . . . . . . . . . . . . . . . . . .
Openat59.5cps.. . . . . . .
Openat58.8cps.. . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
Eastern Wisco
Upper Peninsi
Edison Sault I
Commonweal1
Illinois-Missot
Central Illinoi
Iowa Pool. .
Nebraska Pub
Omaha Public
Missouri Basir
Upper Mississ
I
0. !
0.
0.
0.
0.
0.
0.
1.
SOUTH CENTRAL REGION
Kansas City Power & Light. .
Kansas Power & Light. . . .
Missouri Public Service. . .
Middle South System . . . .
Gulf States Utilities.. . . . .
Central Lousiaina Electric. . .
Kansas Gas & Electric.. . . . . .
Public Service of Oklahoma. . .
Western Farmers Electric Coop
City of Independence. . . . . . . . . . . . .
Southwestern Electric Power. . . . . . .
Oklahonia Gas & Electric . . . . . . . . .
Texas Utilities System. . . . . . . . . . . .
Empire District. . . . . . . . . . . . . . . . . .
St. Joseph Light & Power . . . . . . . . .
South Texas System. . . . . . . . . . . . . .
Springfield, Missouri . . . . . . . . . . . . . .
Plains Electric Gas & Transmission.
Denton, Texas. . . . . . . . . . . . . . . . . . .
Kansas City Municipal . . . . . . . . . . . .
Brownsville Municipal. . . . . . . . . . . .
.
.
.
. .
. .
. .
Studying 58.5 cps . . . . . . . . No. . . . . . . . . . . . . . . . . . .
Open at 58.5 cps . . . . . . . . No. . . . . . . . . . . . . . . . . . .
Stay until untenable. . . . . No . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . . No. . . . . . . . . . . . . . . . . . .
Openat58.5cps.. . . . . . . No. . . . . . . . . . . . . . . . . . .
No policy. . . . . . . . . . . . . . No. . . . . . . . . . . . . . . . . . .
Open at 58.5cps . . . . . . . . No. . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . . No . . . . . . . . . . . . . . . . . . .
Maybe at 58.5 cps . . . . . . . No. . . . . . . . . . . . . . . . . . .
Open if necessary. . . . . . . . No. . . . . . . . . . . . . . . . . . .
Open at 59.4 cps. . . . . . . . No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . . No. . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
Last resort. . . . . . . . . . . . . . No. . . . . . . . . . . . . . . . . . .
Open below 57 cps . . . . . . . No. . . . . . . . . . . . . . . . . . .
Openat58cps.. . . . . . . . . No. . . . . . . . . . . . . . . . . . .
YeS . . . . . . . . . . . . . . . . . . . . No . . . . . . . . . . . . . . . . . . .
Last resort. . . . . . . . . . . . . . No . . . . . . . . . . . . . . . . . . .
Openat59.0cps.. . . . . . . No. . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . . No. . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . . . . . . . . No. . . . . . . . . . . . . . . . . . .
0.
0.
0.
I.
1.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
0.
See footnotes at end of table.
130
Northwest POT
utah POH
Idaho Pov
Grant COI
Puget Sou
Portland (
Tacoma, I
Eugene, V
Montana
Washingtc
Bonneville
Seattle, D’
Pacific Po
Chelan C
California-Ne
Pacific Gz
Southern
Los Angel
Sacramen
Sierra Pat
San Diegc
USBR Re
Arizona-Neva
Arizona I
Tucson G
Arizona E
Arizona F
USBR Rc
Nevada P
Salt Rive]
Rocky Moun
USBR Rc
USBR Rc
USBR Rc
Colorado
So. Color
Colorado.
Public Se
see footnote
TABLE A-5.--Load and generation emcrgmy dro@g +&es-Continued
WEST CENTRAL REGION
I Occasions
hedding Used
.n 1965
Group or System
Eastern Wisconsin Utilities. . . . . . . . . . . . . .
Upper Peninsula Power. . . . . . . . . . . . . . . . .
Edison Sault Electric. . . . . . . . . . . . . . . . . . .
Commonwealth Edison. . . . . . . . . . . . . . . . .
Illinois-Missouri Pool. . . . . . . . . . . . . . . . . . .
Central Illinois Light. . . . . . . . . . . . . . . . . . .
Iowa Pool . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Nebraska Public Power. . . . . . . . . . . . . . . . .
Omaha Public Power. . . . . . . . . . . . . . . . . . .
Missouri Basin Systems . . . . . . . . . . . . . . . . . .
Upper Mississippi Valley Pool . . . . . . . . . . . .
Open Interconnections
on Low Frequency
Drop Generation on Loss
of Load
No. of Occasions
Load Shedding Used
in 1965
Openat58.5cps . . . . . . . .
Has no closed ties.. . . .
Open when capacity is
exceeded.
No...................
O p e n a t 58.5cps.. .
. . . . do. . . . . . . . . . . . . .
Take individual action
below 58.5 cps.
No policy.. . . . . . . . . . . .
. . . .do.. . . . . . . . . . . . . .
No...................
Open at 58.0 cps. . . . . . .
No. . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
0.
8.
0.
No. . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No. . . . . . . . . . . . . . . . . . . .
1.
1.
0.
3.
.......................
ii;:::::::::::::::::::
No . . . . . . . . . . . . . . . . . . . .
3.
WEST REGION
Northwest Power Pool:
Utah Power & Light Co. . . . . . . . . . . . .
Idaho Power Co . . . . . . . . . . . . . . . . . . . . .
Grant County PUD. . . . . . . . . . . . . . . . . .
Puget Sound Power & Lt. Co. . . . . . . . .
Portland General Electric, . . . . . . . . . . . .
Tacoma, Dept. of Pub. Util. . . . . . . . . .
Eugene, Water & Elec. Bd. . . . . . . . . . . .
Montana Power Co. . . . . . . . . . . . . . . . . .
Washington Water Power Co. . . . . . . . . .
Bonneville Power Adm. . . . . . . . . . . . . . .
Seattle, Dept. of Lighting . . . . . . . . . . . . .
Pacific Power & Light Co. . . . . . . . . . . . .
Chelan County P.U.D. . . . . . . . . . . . . . .
California-Nevada Group:
Pacific Gas & Electric Co. . . . . . . . . . . . .
Southern California Edison Co . . . . . . . . .
Los Angeles Dept. of Water & Power. . .
Sacramento Muni. Util. Dist. . . . . . . . . .
Sierra Pacific Power Co. . . . . . . . . . . . . .
San Diego Gas & Elec. Co. . . . . . . . . . . .
USBRReg.2 . . . . . . . . . . . . . . . . . . . . . . .
Arizona-Nevada Group:
Arizona Public Service Co. . . . . . . . . . . .
Tucson Gas 8c Elec. Co. . . . . . . . . . . . . . .
Arizona Electric Power Coop. . . . . . . . . .
Ariiona Power Authority. . . . . . . . . . . . .
USBRReg.3.. . . . . . . . . . . . . . . . . . . . . .
Nevada Power Co . . . . . . . . . . . . . . . . . . . .
Salt River Project . . . . . . . . . . . . . . . . . . . .
Rocky Mountain Power Pool :
USBRReg.4.. . . . . . . . . . . . . . . . . . . . . .
USBRReg.6 . . . . . . . . . . . . . . . . . . . . . . .
USBR Reg. 7. . . . . . . . . . . . . . . . . . . . . . .
Colorado Springs Dept. of Public Util . . .
So. Colorado Power Div . . . . . . . . . . . . . .
Colorado-Ute Elec. Assoc. . . . . . . . . . . . .
Public Service Co. of Colorado. . . . . . . . .
See footnotes at end of table.
No. . . . . . . . . . . . . . . . . .
.....
;4~:::::::::::::: . . . . .
No . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . .
7 times last 5 years.
......................
......................
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
YeS . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
~~.:.::::::::::::::::
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
.......................
Openat59cps.. . . . . . . . .
.......................
.......................
No . . . . . . . . . . . . . . . . . . . .
Openat59cps.. . . . . . . . .
No. . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
.....................
.....................
.....................
No. . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
2 times last 5 years.
1 time last 5 years.
Open at 57 cps . . . . . . . . . .
.......................
.......................
.......................
Openat57cps . . . . . . . . . .
YCS . . . . . . . . . . . . . . . . . . . .
Open at 57 cps . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
......................
......................
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
2 times last 5 years.
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . . .
YeS . . . . . . . . . . . . . . . . . . . .
.......................
.......................
.......................
YeS . . . . . . . . . . . . . . . . . . .
......................
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
0.
0.
0.
0.
0.
2 times last 5 years.
0.
1 time last 5 years.
1 time last 5 years.
0.
0.
3 times last 5 years.
Do.
3.
I.
3.
3.
I time last 5 years.
131
TABLE A-5.-Load and gemration emergency drotiing @&c~Continued
c. Practices in
WEST REGION-Continued
Information
lation to the
in chapter 2 o
ations of the sI
in Volume II
on Reliability
The followi
the surveys cc
Regional Aclv
uniformity in
difficult to prl
mation receive
reserves are a
-
No. of Occasions
Load Shedding Used
in 1965
Open Interconnections
on Low Frequency
Group or System
-New Mexico-Texas Group:
Public Service Co. of New Mexico. . . . .
USBR Reg. 5. . . . . . . . . . . . . . . . . . . . . .
Community Pub. Serv. Co.. . , . . . . , . .
PlainsElecG.&T.Coop... . . . . . . . . . .
El Paso Electric Co. . . . . . . . . . . . . . . . .
No.....
No.....
No.....
No.....
No.....
.......
.......
.......
.......
.......
.....
...*.
.,..*
.....
.....
No . . . . . . . . . . . . . . . . . . .
......................
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
No . . . . . . . . . . . . . . . . . . .
2
times last 5 years.
2 times last 5 years.
Do.
Sylvania Electric Co’s Front Street #5 (52 Mw) Potomac
Elect. Power Co’s Potomac River #3 (102 Mw) and
Benning #9 (20 Mw).
s Manual generator drooping procedures are used at the
USBR Fort Peck, Fort Garrison, and Fort Randall power
plants as required.
4 On overload of a specific transmission line.
s At one plant to avoid instability.
1 Automatic generator tripping schedules at St. Lawrence
covers 1 to 6 units depending on loaded generation levels.
Automatic generator tripping at Niagara under study.
* The following units are equipped for automatic separation including auxiliaries for the purpose of providing a
source of rapid restoration in event of a major shutdown:
Baltimore G & E Co’s Westport #4 (74 Mw), Gould Street
#3 (107 Mw), Riverside Nos. 4 & 5 (8 Mw each), Wagner
Nos. 1 & 2 (140 Mw each), Crane #2 (195 Mw.), Penn-
T ABLE A-C-Spinning
Predominant
Types of
Generation
Group or System
-
-
.-
Emergency Ratf
of Response
Mw/Min.
--
Frequency Bias
Mw/.l Cps
NORTHEAST
reserue practices
REGION
Time Req’d to pick up
10% Max. Cap. in Min.
Minimum Sl
--
A-
Upstate New York Group. . . . . . . . . . .
Steam. . . . . . . . .
230 . . . . . . . . . . .
96 . . . . . . . . . . . .
. 5-8....................
New York State Electric and Gas .
Steam. . . . . . . . .
10 . . . . . . . . . . . .
12 . . . . . . . . . . . .
6......................
summer-Lar
Winter-Large
45 Mw in 4-5
Niagara Mohawk. . . . . . . , . . . . . . .
Steam. . . . . . . . .
10 . . . . . . . . . . . .
48 . . . . . . . . . . . .
5 ,,....,..,,...........
45 hfw in 4-5
Rochester Gas and Electric. . . . . . .
Steam.. . . . . . . .
10 . . . . . . . . . . . .
.............. . , . . . . .
90 Mw in 4-5
Power Authority State of New York.. .
Southeastern N.Y. State Pool. . . , . . . .
Consolidated Edison.. . . . . . . . .
Long Island Lighting. . . . . . . . . . . .
Hydro . . . . . . . .
Steam , . . . . . . .
Steam . . . . . . . .
Steam . . . . . . . .
200 . . . . . . . . . . .
272 . . . . . . . . . . .
183 . . . . . . . . . . .
65 . . . . . . . . . . . .
Incl. in Niagara
Mohawk.
36 . . . . . . . . . . . .
107.4. . . . . . . . .
98 . . . . . . . . . . . .
Incl. in ConEd
1.25. . . . . . . . . . . . . . . . . . .
5......................
5......................
2.......................
4OOMwinlLargest Unit 1
Obligation = 7
Obligation= 1
Central Hudson.. . . . . . . . . Steam . . . . . . . .
14 . . . . . . . . . . . .
6.............
5......................
Obligation = 4
10 . . . . . . . . . . . .
3.4. . . . . . . . . . .
5......................
Obligation = I
225 . . . . . . . . . . .
116 . . . . . . . . . . .
49& of peak ir
45 . . . . . . . . . . . .
23 . . . . . . . . . . . .
1st 6% in 5 minutes,
next 4% in 20 min. to
1 hour.
1st 6% in 5 minutes,
next 40/o requires add’l.
machine commitment.
5......................
1st 6% in 5 minutes,
next 470 may require
starting add’l. units.
Orange and Rockland. . . . . . .
Steam . . . . . . .
New England System. . . . . . . . . . .
Steam. . . . . . . .
Boston Edison Co. . . . . . . . . . . . . .
Steam. . . . . . . .
Central Maine.. . . . . :. . . . . . .
CONVEX Group. . . . . .
Steam. . . . . . . .
Steam. . . . . . . .
See footnotes at end of table.
132
.
.
.
.
.
14 . . . . . . . . . . . .
62 . . . . . . . . . . . .
.
.
..............
42........: . . .
4y0 of peak ir
4y, of peak il
4o/o of peak ir
c. Practices in Spinning Reserve
Information concerning spinning reserves in relation to the Northeast power faiiure is included
in chapter 2 of this report. More general considerations of the subject may be found in chapter 5 and
in Volume II, Report of the Advisory Committee
on Reliability of Electric Bulk Power Supply.
The following table summarizes the responses to
the surveys conducted for the Commission by the
Regional Advisory Committees. Lack of complete
uniformity in some replies to the survey has made it
difficult to prepare a simple summary of the information received. Furthermore, the levels of spinning
reserves are affected by factors such as the sizes of
units, the combinations of unit types, the system size,
and the capacity of interconnections with neighboring systems.
The survey results indicate that approximately
30 percent of the systems or operating groups maintained spinning reserves equal to or greater than
the largest generating unit, 24 percent carried less
than the equivalent of the largest unit, and 46 percent scheduled reserves as a percentage of peak load.
Of the latter group, spinning reserves varied from 3
percent to 10 percent of system peak.
Since the Northeast failure, more attention has
been given to allocating reserves among a larger
number of units to obtain faster system response and
wider geographical distribution of reserve capacity.
reservepractices
REGION
T
Minimum Spinning Reserve and Time
Required
I
Non-Spinning Reserve and Time
Required
Summ~Largest Unit + 50 Mw (260 Mw) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Winter-Largest Unit+90 Mw (300 Mw)
(1)
45Mwin4-5Min . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..*.................
45Mwin4-5Mln . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9OMwin4-5Min . . . . . . . . . . . . . . . . . . ..I
Spinning Reserve Unit Allocation
PrXtkXS
No uniform group policy.
Maintain 7 or 8 Mw on each unit
consistent with area power flow
and security.
System security determines day to
day unit commitments and reserve
distribution schedules.
Economy loading.
4QOMwinl-2Min . . . . . . . . . . . . . . . . . . .
Largest Unit Loading+200 Mw. . . . . . .
Obligation = 73.3y0 available in 5 minutes
Obligation= 18.8% available in 1 minute..
........................ . . . . . . . .
........................ . . . . . . . . No uniform pool policy.
........................ . . . . . . Spread throughout based on response.
Economy loading with high limit
........................ . . . .
Obligation=4.6% available in 5 minutes. .
........................
control.
. . . . . . . . Maintain at least 15 Mw on the
largest unit (280 Mw).
Economy loading.
Obligation=3.30/, available in 2-4 minute
4Q/oofpeakin5min.s . . . . . . . . . . . . . . . . .
2y0 of peak in 5 minutca s.
4%ofpeakin5min.s.. . . . . . . . . . . . . . . .
270 of peak in 5
40/0ofpeakin5min.s.. . . . . . . . . . . . . . . .
4%ofpeakin5min.s.. . . . . . . . . . . . . . . .
2% of peak in 5 minutes 2.
2% of peak in 5 minutes 2.
No uniform group policy.
minutes *.
Unita loaded for maximum economy.
....
....
Economic dispatch.
Economic dispatch consistent with
area security.
133
TABLE A-6.-S’inning
-
NORTHEAST
-
Group or System
Time Req’d to pick up
10% Max. Cap. in Min.
Emergency Rate Frequency Bia L.9
Mw/.l Cps
of Response
MwJMin.
Predominant
Types of
Generation
--
Minimum Spin;
--
New England System-Continued
New England Electric. . . . . . . . . .
Steam . . . . . . . .
40.............
51...........
New England Gas and Elect&. .
Steam . . . . . . . .
18.. . . . . . . . . . . .
Incl. inN.E.
Electric.
Public Service of New Hampshire
Central Vermont Public Service..
Steam . . . . . . . .
Purchase power
. .
1-5 . . . . . . . . . . . . . . . . . . . .
8. . . . . . . . . . . . . . . . . . . . . .
Green Mountain Power. . . . . . . . . . . .
Purchase. . . . . .
24............. . . . . . d o . . . . . . .
9 . . . . . . . . . . . . . . 1ncl.inN.E.
Electric.
6.............. . . . . d o . . . . . . . .
.
2-3 . . . . . . . . . . . . . . . . . . . .
Eastern Utilities.. . . . . . . . . . .
Penna-N.J.-Maryland System. . . . . . .
Steam. . . . . . . . .
Steam. . . . . . . . .
7.. . . . . . . . . . . . . . .do.. . . . . . .
47.............. 190..........
. .
. .
10 . . . . . . . . . . . . . . . . . . . . .
15-30 . . . . . . . . . . . . . . . . . .
1st 6% in 5 minutes,
next 4% unknown.
5-20...................
.
SOUTHEAST
-
Florida Group. . . . . . . . . . . . . . . . . . . .
Steam. . . . . . . . .
100-150 . . . . . . . .
98 ............
2-4............
CARVAPool.....................
Steam. . . . . . . . .
Approx. 200. . . .
..............
upto15min...
Carolina Power and Light . . . . . . .
Duke Power Co . . . . . . . . . . . . . . . .
Steam. . . . . . . . .
Steam. . . . . . . . .
50-75 . . . . . . . . . .
50 . . . . . . . . . . . . .
34 . . . . . . . . . . . .
58 . . . . . . . . . . . .
10 . . . . . . . . . . . . .
6. . . . . . . . . . . . . .
South Carolina Electric and Gas.
Virginia Electric and Power. . . . .
Steam. . . . . . . . .
Steam. . . . . . . . .
................
50 . . . . . . . . . . . . .
15 . . . . . . . . . . . .
59 . . . . . . . . . . . .
1-15 . . . . . . . . . . .
8.5 . . . . . . . . . . . . .
Southern Services. . . . . . . . . . . . . . . . .
Steam . . . . . . . .
108 . . . . . . . . . . . .
132 . . . . . . . . . . .
8. . . . . . . . . . . . . .
Tennessee Valley Authority . . . . . . . . .
Steam. . . . . . . . .
Approx. 250. . . .
162 . . . . . . . . . . .
.......
EAST CENTRAL
-
-7
-
1st 8’% in 3-5 minutea,
next 10% in l-8 hours.
1st 5% in 3 minutcs,
next 10% in 4 hours.
17.....................
American Electric Power. . . . . . . .
Steam. . . . . . . . .
50-100 . . . . . . . . .
140 . . . . . . . . . . . .
Allegheny Power. . . . . . . . . . . . . . . . . .
Steam. . . . . . . . .
58 . . . . . . . . . . . . .
38 . . . . . . . . . . . . .
Cincinnati Gas and Electric.. . . .
Steam . . . . . . . .
24 . . . . . . . . . . . . .
36 . . . . . . . . . . . . .
Cleveland Electric Illum. . . . . . .
Steam. . . . . . . . .
33 . . . . . . . . . . . . .
44 . . . . . . . . . . . .
1st 3% in 2 minutes,
next 10% in 2 hours.
Columbus and South Ohio Electric. . .
Steam . . . . . . . .
20-35 . . . . . . . . . .
20 . . . . . . . . . . . . .
4......................
Consumers Power-Detroit Edison. . .
Steam. . . . . . . .
300 . . . . . . . . . . .
ill...........
20.....................
Detroit Public Lighting. . . . . . . . .
See footnotes at end of table.
Steam. . . . . . . . .
13-27 . . . . . . . . .
..............
134
reserve practices-Con
REGION-Contin
.
.
.I
4yo of peak in 5
I
4% of peak in 5
I
4oj, of peak in 5 I
4% of peak in 5
tion.
43$& of req’d. r
purchase.
4oj, of peak in 5 1
Largest liability,
REGION
Largest unit ava
quency change
“/3 of largest unit
Refer to Pool. . ,
Refer to Pool.
Refer to Pool s. .
Refer to Pool s.
Largest unit pra
236 minutes.
2%yo of load+!
Mw but never
REGION
100 Mw (f< of la
minutes.
115 Mwin2mi
60 Mw (5yo of:
33 Mw (K of I;
Mw via inte
one minute.
40-70 Mw (% to
2 min.
4 5 0 M w t”/3 c
minutes.
135, . . . . . . . . . . . . .
267-7810
L-Spinning
RTHEAST
r pick up
p. in Min.
rmruc practices-Continued
REGION-Continued
-
Non-Spinning Reserve and Time
Required
Spinning Reserve Unit Allocation
Practices
4%ofpeakin5min.s. . . . . . . . . . . . . . . . .
2% of peak in 5 minutes s. . . . . . . . . .
4%ofpeakin5min.s ..,..............
2% of peak in 5 minutes *. . . . . . . . . .
4%ofpeakin5min.s. . . . . . . . . . . . . . . . .
4% of peak in 5 minutes via interconnec-
2yn of peak in 5 minutes s.. . . . . . .
2% of peak in 5 minutes via interconnections.
.................................
Units loaded for maximum economy
consistent with area security.
High pressure units are max. base
loaded-Reserve maintained on
low pressure units.
Maintain 20% on the largest unit.
Not applicable.
Minimum Spinning Reserve and Time
Required
--
lutes,
mm.
..........
..........
..........
..........
..........
..........
tion.
43% of req’d. reserve available through
purchase.
40/,ofpeakin5min.s . . . . . . . . . . . . . . . . . .
Largest liability, presently 500 Mw . . . .
2% of peak in 5 minutess. . . . . . . . . .
287 Mw available in 30 minutes. . .
.....Do.........................
Units loaded for maximum economy.
Economy loading consistent with
system security.
-
UTHEAST
..........
..........
..........
..........
..........
..........
...... ....
..........
REGION
-
Largest unit available before 0.5 cps frequency change.
IyZ of largest unit available in 10
X of largest unit. . . . . . . . . . . . . .,. .
;H of largest unit available in 10
50/, on 100 Mw units and larger.
7Hg/, on 75 Mw units.
10% on 50 Mw units and smaller.
No uniform pool policy.
RefertoPools . . . . . . . . . . . . . . . . . . . . . . . . .
RefertoPools . . . . . . . . . . . . . . . . . . . . . . . . .
Refer to Pool . . . . . . . . . . . . . . . . . . . . .
Refer to Pool. . . . . . . . . . . . . . . . . . . . .
Economic dispatch.
Economic loading consistent with
area security.
Widespread distribution.
Widespread distribution.
Largest unit presently 270 Mw available in
2% minutes.
2% ye of load+j/l of largest liability+300.
Mw but never less than largest 1iability.s
...............................
minutes.
minutes.
1Refer to Pool.. . . : . . . . . . . . . . . . . .
Refer to Pool. . . . . . . . . . . . . . . . . . . . . . . .
Refer to Pool. . . . . . . . . . . . Refer to Pool.. . . . . . . . . . . . . . . . . . .
Widespread distribution consistent
with economy loading.
Spread over a large number of hydro
units whenever possible; otherwise
operate steam units at reduced
loading.
CENTRAL
ninutes,
l-8 hours.
nutes,
4 hours.
nutes,
2 hours.
..........
..........
i
..........
LEGION
-
100 Mw (>/6 of largest unit) available in l-2
minutes.
115Mwin2minutes . . . . . . . . . . . . . . . . . .
60Mw(5’%ofpeak)in2~min
.........
560 Mw (96 of largest unit) available
in 10 minutes.
19 Mw interruptible in one minute.. .
Distribution proportional to unit’s
ability to respond.
Economic dispatch and unit response ability.
125 Mw in 15 minutes.. . . . . . . . . Economic dispatch with fixed Mw
assignment.
Fixed Mw assignment.
67 Mw (s of largest unit + 50-200
Mw via interconnections available
in 1 min.
73 Mw in 10 minutes.. . . . . . . . . . . . . . Economic dispatch.
33 Mw (g of largest unit + 50 Mw-200 /
Mw via interconnections) available in
one minute.
4@70 Mw (K to 34 of largest unit) avail. in
2 min.
450 Mw (# of two largest units) in 10
minutes.
220 Mw (s of two largest units) in 10
min.
20-40 Mw in 134 minutes.. . . . . . . . . . .
31 Mw interruptible in 2 minutes. . . .
267-7810-M-10
Economic dispatch consistent with
area security and widespread
distribution.
Fixed Mw assignment.
135
TABLE A-G.-Spinn
Predominant
Types of
Generation
Group or System
_-
.-
1
1
I
/
EAST CENTR
Emergency Rate
of Response
MwjMin.
-
Time Req’d to pick up
10% -Max. Cap. in Mii
Frequency Bias
Mw/.l Cps
--
Steam . . . . . . . . .
lo-13 . . . . . . . . .
. 20 . . . . . . . . . . . .
East Kentucky REA . . . . . . . . . . . . . . . .
Steam. . . . . . . . . .
..............
. . ..............
Indianapolis Power and Light . . . . . . . .
Steam. . . . . . . . . .
20 . . . . . . . . . . . .
20 . . . . . . . . . . . .
Kentucky Utilities . . . . . . . . . . . . . . . . . .
Lansing Water and Light . . . . . . . . . . . .
Steam. . . . . . . . . .
Steam. . . . . . . . . .
12 . . . . . . . . . . . .
..............
26. . . . . . . . . . . .
..............
Louisville Gas and Electric. . . . . . . . . .
Steam. . . . . . . . .
38 . . . . . . . . . . . .
Northern Indiana Public Service. . . . .
Steam. . . . . . . . .
90 . . . . . . . . . . . .
Ohio Edison Co . . . . . . . . . . . . . . . . . . . .
Steam. . . . . . . . . .
OVEC . . . . . . . . . . . . . . . . . . . . . . . . . . .
1st 4% in 14 minutes,
next 10% in 15-24 H
Included in Kentuc
30 . . . . . . . . . . . .
..............
1st 5% in s minute . . . .
360 . . . . . . . . . . .
48 . . . . . . . . . . . .
1st 7% in 5 minutes,
next 10% in 2-3 hour
Steam. . . . . . . . .
. ..............
20 . . . . . . . . . . . .
Public Service Co. of Indiana. . . . . . . .
Steam. . . . . . . . .
150 . . . . . . . . . . .
38 . . . . . . . . . . . .
Southern Indiana Gas and Electric. , . .
Toledo Edison Co. . . . . . . . . . . . . . . . . .
Steam. . . . . . . . . . .
25::::::::::::
Steam. . . . . . . . .
. ..............
.
.
1st 5% in 36 minute,
next 10% in 6 hours.
14 . . . . . . . . . . . .
Included in Kentuc
Owensboro Municipal. . . . . . . . . . . . . .
-
-
-
Southwest Group. . . . . . . . . . . . . . . . . . .
West Texas Utilities . . . . . . . . . . . . .
Kansas Power and Light. . . . . . . . .
Kansas City Power and Light. . . . .
Kansas Municipal. . . . . . . . . . . . . . .
St. Joseph Light and Power. . . . . .
City of Independence . . . . . . . . . . . .
Western Farmers Coop. . . . . . . . . .
Missouri Public Service Co. . . . . . .
Springfield, Mo. . . . . . . . . . . . . . . . .
Denton, Texas. . . . . . . . . . . . . . . . . .
Brownsville Municipal. . . . . . . . . . .
South Central Group. . . . . . . . . . . . . . .
Ivijddle South Utilities . . . . . . . . . . .
Kansas Gas and Electric. . . . . . . . .
Central Louisiana. . . . . . . . . . . . . . .
Empire District. . . . . . . . . . . . . . . . .
Gulf States Utilities. . . . . . . . . . . . .
Oklahoma Gas and Electric. . . . . .
Public Service Co. of Oklahoma.
Southwestern Electric Power Co.
See footnotes nt end of table.
136
SOUTH CENTR.
Upto30min.. . . . . . . .
.............................
.............................
...............
...............
.
...............
.
..
.
...............
..
..
...............
...............
...............
. .
...............
.
...............
12 . . . . . . . . . . . .
19 . . . . . . . . . . . .
47 . . . . . . . . . . . .
5.6. . . . . . . . . . .
2.............
0.25. . . . . . . . . .
2.............
..............
..........
ss . . . . . . . . . . . .
..............
25 . . . . . . . . . . . . . . . . . . .
3....................
13 . . . . . . . . . . . . . . . . . . .
5. . . . . . . . . . . . . . . . . . . .
5.................: . .
Inst. . . . . . . . . . . . . . . . . .
4....................
30 . . . . . . . . . . . . . . . . . . .
25 . . . . . . . . . . . . . . . . . . .
Inst. . . . . . . . . . . . . . . . . .
.....................
Steam..........................
195 . . . . . . . . . . .
Upto 1 5 m i n . . . . . . . . .
/66 . . . . . . . . . . . .
0.5. . . . . . . . . . . . . . . . . .
10 . . . . . . . . . . . . . . . . . . .
10 . . . . . . . . . . . . . . . . . . .
12 . . . . . . . . . . . . . . . . . . .
8. . . . . . . . . . . . . . . . . . . .
2.5. . . . . . . . . . . . . . . . . .
8....................
15 . . . . . . . . . . . . . . . . . . .
..............
..............
..............
..............
.
.
....................
+OMw(XtimcsI
3-4 minutes.
‘tilities Companl
Minimum of 50
available in 23
50 Mw (s time
minutes.
Cover largest loa
minute.
75 Mw (25% o
peak) in two t
45 Mw plus ap
connections tc
able in 34 min
120 Mw (H of 1
minute.
136 Mw availal
75Mw(5%of:
. . . . . . . . . .
25 Mw (5 Mw
tingencies available in c
Utilities Cornpa
REGION
-
Approx. 100. . .
Steam..........................
Minimum Spin
-
-
-
REGION-Contil
-
--
Duquesne Light Co. . . . . . . . . . . . . . . . .
.
reserve practices-Cc
20. . . . . . . . . . . .
5.............
4.............
42 . . . . . . . . . . . .
24 . . . . . . . . . . . .
18 . . . . . . . . . . . .
16 . . . . . . . . . . .
.
3% of peak at
frequency fa
. . . .do . . . . . . .
. . . .do . . . . . . .
. . . .do . . . . . . .
. . . .do . . . . . . .
. . . .do.. . . . . .
. . . .do . . . . . . .
. . . .do.. . . . .
. . . . do . . . . . .
. . . . do . . . . . .
. . . .do . . . . . .
Considers Cer
connection 1
ning reserve
3% of peak i
frequency E
. . . do . . . . . .
. . . do . . . . . .
. . . do . . . . . .
. . . do . . . . . .
. . .do.. . . . .
. . .do . . . . . .
. . . do . . . . . .
. . . do . . . . .
roerue practicts-Continued
REGION-Continued
-
Minimum Spinning Reserve and Time
Required
-
--
40 Mw (s times 6% of peak less 30 Mw) in
3-4 minutes.
Utilities Company
Minimum of 50.Mw over peak load hour
available in 2% minutes.
(
Non-Spinning Reserve and Time
Required
‘1 60 MW (g times 4: of largest unit) in 5
Spinning Reserve Unit Allocation
Practices
--
20 Mw (45 times 6% of peak less 3( )
Mw) in 10 minutes.
Economic dispatch.
20 Mw interruptible in 5 minutes. .
Economic dispatch with high limit control to insure a widespread regulating
margin.
Fixed Mw assignment.
49Mwin5minutes.. . . . . . . . . . . . . .
minutes.
Cover largest load on any single unit in one I Mw in 30minute.s.. . . . . . . . . . . . . .
minute.
75 Mw (25% of largest unit plus 25% of 60Mwin7minutes.. . . . . . . . . . . . . .
peak) in two minutes.
45 Mw plus approx. 138 Mw from inter- N o n e . . . . . . . . . . . . . . . . . . . . . . . . . . .
connections to cover largest unit-available in 3/z minute.
120 Mw (2/5 of largest unit) available in yS 60 Mw interruptible (s of largest
minute.
unit) available in 5 minutes.
136 Mw available immediately.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
75 Mw (5yc of peak) available in yZ minute
Economic dispatch with high limit control whenever possible.
Economic dispatch with distribution
proportional to unit capacity.
Distribution proportional to unit’s
ability to respond.
90% in proportion to capability and
10% via economic dispatch.
Distribution proportional to power
participation ratio.
Economic dispatch.
None...........................
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .................................
25 Mw (5 Mw regulation + 13 Mw contingencies +7 Mw bias obligation)
available.in one minute.
Utilities Company
kAL 1 REGION
-i ,
,..
..
L
I”
1..
ST
‘I
II
....
,..
...
...
...
53 Mw available in 15 minutes.
Maintained on 3 units consistent
with economic dispatch and unit’s
response rate.
-
-
-
-
3% of peak available automatically when 3% of peak available in 10 minutes. .
frequency falls to 59.5 cps.
. . . ..do................................
.do. . .
. . . ..do................................
.do.
. . . ..do................................
.do.
..
. . . ..do................................
.do. .
..
..
. . . ..do................................
..
.do. . .
.
..
.
. . . ..do................................
..
.
..
.do.
. . . ..do................................
.do. . .
- . . . ..do................................
.do. . .
..
..
..
.do................................
.
.do. .
.
..
.
i::::.do . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.
.do.
Considers Central Power and Light’s inter.
.
.do.
connection worth 10 megawatts of spinning reserve.
. do........................
3yo of peak available automatically when
frequency falls to 59.5 cps.
.
. .do.. . . .
..
..
. . ..do................................
. .do. . .
.
..
.
...’d o . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.
..do................................
.do . . . . .
..
.
. .do . . . .
.
‘
... d o . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.
. .do . . . . .
.... d o . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. .do . . . .
.
...’d o . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.
. .do.. . . .
..
...’d o . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . .do................................
. .do . . . .
.
Distribution based on ability to
respond before 59.5 cps.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
137
TABLE A-6.---@innir
SOUTH CENTRA
Time Req’d to pick up
10% Max. Cap. in Min.
Frequency Bias
Mw/.l Cps
SouthTexasSystem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
lOO............ . . . . . . . . . . . . . . . . . . . . . . .
ve practices--Con!
;ION--Continu
Minimum Spinni
RI
lrgest u n i t .
Texas Utilities System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ugest unit + 10
I
W E S T CENTRA
,GION
-
Steam..
Steam.. .
50 . . . . . . . . . . . .
100 . . . . . . . . . . .
131............
69 . . . . . . . . . . . . .
15 . . . . . . . . . . . . . . . . . . .
5.....................
WOMW.. . .
,argest u n i t ‘.
Steam...
. Hydro. .
Steam...
Steam...
Steam...
. Steam...
Steam..
Hydro . .
. Steam...
..............
......
iii::::: ......
20. . . . . . . . . . . .
..............
..............
........
ii,::: . . . . . . . .
85 . . . . . . . . . . . .
.............. .
.......
iii::::: .......
9.7. . . . . . . . . . . .
44 . . . . . . . . . . . . .
............
is . . . . . . . . . . . . .
30 . . . . . . . . . . . . .
69 . . . . . . . . . . . . .
5..................
5..................
5....................
3....................
,&4OMw’....
0%.
.
.
.
/z of largest unit
Commonwealth Edison..
Eastern Wisconsin UtiIities
Upper Peninsula Power. .
Edison Sault Electric. . . . .
Ill.-MO. Pool. . . . . .
Central Ill. Light.
Iowa Pool.. . . . .
Omaha Public Power. .
Nebraska Public Power. . . .
Missouri Basin System. . .
Upper Mississippi Valley.
.
.
.
.
.
.
.
.... .
.
.
.
.
.
.,....
.....................
0.85. . . . . . . . . . . . . . . . .
30 . . . . . . . . . . . . . . . . . . .
O~o+20 Mw..
,argest u n i t .
;y& . . . . .
.
i% or largest un
Largest unit.
-
WE!
EGION
-
Northwest Power Pool. . . . . . . . . . . . . .
Utah Power & Lt. Co . . . . . . . . . . .
Idaho Power Co. . . . . . . . . . . . . . . .
Grant County P.U.D. . . . . . . . . . . .
Puget Sound Power & Lt. Co. . . .
Portland General Electric Co. . . . .
Tacoma, Dept. of Pub. Util. . . . . .
Eugene, Water & Elec. Bd. . . . . . .
Montana Power Co . . . . . . . . . . . . .
Wash. Water Power Co. . . . . . . . .
Bonneville Power Adm . . . . . . . . . .
Seattle, Dept of Lighting. . . . . . .
Pacific Power and Light Co. . . . .
Chelan County P.U.D. . . . . . . . . .
Army . . . . . . . . . . . . . . . . . . . . . . . .
California-Nevada:
PacificGasandElectricCo . . . . . .
Southern California Edison Co. . .
Hydro . . .
.
.
138
...............
...............
...............
...............
...............
...............
...............
...............
...............
...............
...............
..............
..............
..............
...............
.............
.............
.............
.............
.............
-I
.............
........
.....
.............
...............
.
.....................
.....................
.....................
.....................
.....................
............... . . . . . . . . . . . . . . .
............... . . . . . . . . . . . . . . .
100 . . . . . . . . . . . .
90 . . . . . . . . . . . . .
............... ......
.....................
...............
................
...............
...............
...............
...............
...............
14 . . . . . . . . . . . .
............... ......
.....................
.....................
.....................
...............
...............
...............
...............
...............
...............
...............
...............
..............
30 . . . . . . . . . . . .
15 . . . . . . . . . . . .
6.............
..............
..............
5 ...........
1;: . . . . . . . . . . .
.
.
.
.
.
Los Angeles Dept. of Water and Power. . . . . . . . . . .
Sacramento Muni. Util. Dist. . . . . . . . . . . . . . . . . . . .
Sierra Pacific Power Co. . . . . . . . . . . . . . . . . . . . . . . . .
SanDiegoGas & Elec. C o . . . . . . . . . . . . . . . . . . . . . .
Rocky Mountain Power Pool.
USBR Region 6. . . . . . . . . . . .
USBR Region 4. . . . . . . . . . . .
USBR Region 7. . . . . . . . . .
Colorado Springs Dept. of Pub.
Southern Colorado Power Div.
Colorado-Ute Elec. Assoc. . . . .
Public Service Co. of Colorado.
See footnotes at end of table.
.
. . . . . . . . .
. Hydro....
............
. Hydro . . . .
Util. . . . . . . . .
............
............
............
.
.
..
.
.
..
.............
.....................
.....................
.....................
.....................
.....................
.........
............
.....................
........
.............
No uniform pool
l’i;B.. _......
200-300 Mw
Normally 30%.
.
l%... .
1%‘
.
1y .
.
,.....
. .
Relies on intero
5y&. .
.
.
Largest unit.
15yo
6,
1%‘
. . . . . .
2%7., . . . . . .
Relies on intcrc
1 5 % . . .
Largest unit pb
5% of daily pe
unit.
Largest unit.
Included with
Largest unit.
Largest units n
No uniform pc
Largest unit 01
107,. . . .
10Yo.. .
.
Relies on inter
10%
7.
.
Relies on intet
Largest contin
ftrz~e practices-Continued
.EGION-Continued
Spinning Reserve Unit Allocation
Practices
Non-Spinning Reserve and Time
Required
Minimum Spinning Reserve and Time
Required
-
Largest unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Distribution based on ability to
respond befoke 59.5 cps.
Each unit is limited to 10% or 25
Mw, whichever is smaller.
Largest unit + 100 Mw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
lEGION
20&300 Mw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Largest unit 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
364OMw’
........................... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
50% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
j$oflargeatunit6.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
lOQ/o+20Mw . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Large&unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..... ...................................................................
5% orlargestunit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Largestunit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Minimum of 3% on each unit.
Economic dispatch or widespread
distribution.
.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
Do.
LEGION
-
No uniform pool policy. . . . . . . . . . . . .
..................................
..................................
..................................
..................................
...................................
..................................
..................................
..................................
..................................
..................................
..................................
..................................
..................................
..................................
No uniform pool policy. . . . . . . . . . . . . . . .
l%‘
................................
200-300 Mw . . . . . . . . . . . . . . . . . . . . . . . . .
Normally 30%. . . . . . . . . . . . . . . . . . . . . . .
1% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1707 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Relies on interconnections. . . . . . . . . . . . . .
5% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Largestunit . . . . . . . . . . . . . . . . . . . . . . . . . .
15%6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
l%‘
................................
2%7 ................................
Relies on interconnections. . . . . . . . . . . . . .
15% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Largest unit plus largest line plus 90 Mw
5oJ, of daily peak but not leas than larges
unit.
Largest unit. . . . . . . . . . . . . . . . . . . . . . . . . .
Included with PG &E. . . . . . . . . . . . . . . . . .
Largest unit. . . . . . . . . . . . . . . . . . . . . . . . . .
Largest units minus 5y0 of daily peak. . .
No uniform pool policy. . . . . . . . . . . . . . . .
‘kargest unit or 5%. . . . . . . . . . . . . . . . . . . .
10% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10% . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Relies on interconnections. . . . . . . . . . . . . .
loo/,1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Relies on interconnections. . . . . . . . . . . . . . .
Largest contingency plus load swings. . . . .
No unifcmn pool policy.
Widespread distribution.
..................................
..................................
t
..................................
..................................
..................................
..................................
.
.
.
.
.
..................................
..................................
..................................
..................................
..................................
..................................
..................................
..................................
139
TABLE A-6.S’innin~
-
7
Emergency Rate Frequency Bias
Mw/.l Cps
of Response
Mw/Min.
Predominant
Types of
Generation
Group or System
WES’l
Time Req’d to pick up
10% Max. Cap. in Min.
rem practices-CO
EGION-Contin
Minimum Spin
-.
...............................
...............................
...............................
...............................
...............................
...............................
NewMexico-Texaz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Public Service Co. of New Mexico . . . . . . . . . . . . . . .
USBR Reg.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Community Public Service Co. . . . . . . . . . . . . . . . . .
PlainsElec.G&TCoop.. . . . . . . . . . . . . . . . . . . . . .
El PasoElectric Co . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Arizona-Nevada :
Arizona Public Service . . . . . . . . . . . . . . . . . . . . . . . . . .
Arizona Electric Power. . . . . . . . . . . . . . . . . . . . . . . . .
Tucson Gas & Elec. Co. . . . . . . . . . . . . . . . . . . . . . . .
USBRR eg. 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Nevada Power Co. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Salt River Project . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
..........
.......... . . . . .
.......... . . . . .
..........
.......................
.......................
45 ............ .......................
See Arizona Put7 dit c Service. . . . . . . . . . . . . . . .
.....................do . . . . . . . . . . . . . . . . . . . . . . . .
...
. . . . . . . . . . . . . . . . . . . . . do . . . . . . . . . . . . . . . . . . . . . . . .
...
. . . . . . . . . . . . . . . . . . . . . do . . . . . . . . . . . . . . . . . . . . . . . .
. . . . . . . . . . . . . . . . 33............. . . . . . . . . . . . . . . .
................
................
Largest unit. . .
See Arizona Pub
d
o
.
. . ..do.........
do. . . .
Largest unit.
1 Rely on PASNY contract for approximately 125-165
Mw spinning capacity.
* 40% of an amount equal to total of spinning plus non-
spinning reserve must be available within one minute.
s Quick start capacity incIuded in spinning reserve.
* Includes a small amount of quick starting capacity.
5 Depends on ir
lr additional 3/2 1
eludes 36 Mw i
d. Restoration of System Services
Further information concerning the needs for power
to insure safe shutdown and prompt restarting of
generating units appears in chapter 5 and in
Volume II.
I
In recent years, little thought had been given in
many instances to the idea that a generating plant
on a large interconnected system would find itself
without station power to shut down safely and Rstart quickly. The power failure proved otherwise.
Since that time, provisions have been planned or
ccomplished 1
mergency pow
xe were depel
The replies 1
2storation of s
@em power i
ent of those r
ions with othc
tartup power.
Iart on hydro
This section is concerned with the sources of
power available for restarting generating units and
restoring power systems to operation following a
widespread outage involving the loss of system
power or other usual sources of station service supply. Seine of the problems encountered in the
Northeastern part of the United States on November 9, 1965, are discussed in chapter 2 of the report.
TABLE
A-7.-Practices for rapid restoration of service in the event of total loss of system power or when such loss of ytem power is imminnd
TABLE A - 7 . -
Means of Obtaining Emergency Startup Power
System or Pool
-
Interconned tt i o n s withL
other systen ls
-
*;*zi””
I
Gasoline or
Diesel Engines 1
System or Pot
1
- -
-.
.Northcast Region
‘b+ut region4
Boston Edison Co. .
Central Hudson Gas
& ElectriC. . . . . .
Central Maine
Power Co. . . . . . . .
Central Vermont
Pub. Serv. . . . . . . .
Connecticut Light
82 Power. . . . . . .
Consolidated Edison
0fN.Y.. . . . . . . . .
Green Mountain
Powercorp......
140
............
.............
X
X
X
X
X
............
X
X
,X
............
...............
X
............
X
...............
.............
X
X
...............
.............
X
X
...............
.............
Under study.
............
. . ...............
he Hartford Ele
LightCo......
ong Island Ligh
c
o
.
.
‘ew England Ele
tric System. .
lew England Ga
& Elec. A s s n
I.Y. State Electr
& Gas. . . .
fiagara Mohawk
Power Corp. . .
rcscrvc practices-Continued
REGION-Continued
Non-Spinning Reserve and Time
Required
Minimum Spinning Reserve and Time
Required
Spinning Reserve Unit Allocation
Practices
_ .-
.
....
....
....
....
....
. . .
....
....
. .
...
kb...
10% . . . . . .
10% . . . . . .
10% . . . . . .
10% . . . . . .
10% . . . . . .
10% . . . . . .
......................................................
......................................................
........................................ ..............
......................................................
......................................................
......................................................
Largestunit . . . . . . . . . . . . . . . . . . . . . . . . . . .
See Arizona Public Service. . . . . . . . . . . . . .
... ..do . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . ..do . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . ..do . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Largest unit. . . . . . . . . . . . . . . . . . . . . . . . . . .
3
I--
.
.
.
.
.
.
. .
.
...
...
. .
..
. .
.
.
. .
...
...
.
.
...
...
...
...
..
.
.
.
.
interruptible by phone call.
0 Includes interruptible loads.
7 Includes quick starting capacity.
6 Depends on interconnections and reciprocal exchange
for additional >h of largest unit. Ill.-MO. spinning reserve
includes 36 Mw interruptible by pushbutton and 50 Mw
c
dy.
)wer
g of
1 in
gas or diesel engine generators, 20 percent have gas
turbines, 18 percent isolate units, and 11 percent
store steam for quick starting. In addition ,to these
arrangements, 5 percent have additional emergency startup plans under study, and 7 percent have
gas turbines on order.
The following table shows the responses to questionnaires distributed by the Regional Advisory
Committees to obtain information on restarting
practice.
accomplished to insure a dependable source of
emergency power for many stations which heretofore were dependent upon network connections.
The replies to the survey of practices for rapid
n in I restoration of service in the event of total loss of
llant
system power indicate that approximately 30 pertself
cent of those reporting expect to use interconnecI l-etions with other systems as sources of emergency
vise.
startup power. About 45 percent depend at least in
1 or
part on hydro facilities. Twenty-six percent have
I
zinenl
1
TABLE
A-7.-Practices for rapid restoration of service in the event of total loss of system power or when such loss of system power is
imminenl-Continued
I
I
System or Pool
I
.... ,...
.... ....
.... ....
. .
. .
. . . ....
Means of Obtaining Emergency Startup Power
-i--
Interconnecttions with
other systems
Gasoline or
Diesel Engines Gas Turbines
owk2dro
I
Separating Steam Storing Steam
Unit from System in Boilers for
with Auxiliaries Quick Starting
Nar~hcast region-Con.
IThe Hartford Elcc.
Light Co. . . . . . .
Long Island Lighting
co...............
New England ElecI tric System. . . . . . . . . . .
New England Gas
&Elcc.Assn . . . . . . ._..
N.Y. State Electric
&Gas . . . . . . . . . . . . . . . .
Niiara Mohawk
I Power Corp. . . . . . . .
..............
. . . . ...........................
.
.....,..
.
.
.
.
.
X
.
.
.
x
.
.
.’
::
..............
.............
..............
.I
Taking steps to insure cranking power to all stations.
.
. .............
X
x
.............................
x
.............................
.I
x
141
TABLE A-7.-Practices
TABLE
for rapid restoralion of service in the cven~ of total loss of system power or whm such loss of systm power is
A-7.-
imminent-Continued
Means of Obtaining Emergency Startup Power
System or Pool
-
System or Po
Gasoline or
Hesel Engine!
lnterconnecttions with
other systems
Gas Turbines
--
SC zparating Steam
U[nit from System
Yvith Auxiliaries
- -
Ltoring Steam
n Boilers for
luick Starting
East Central Regio
Northeast Region-Con
Orange & Rockland
utilities, Inc.. . .
Western Massachusetts Electric. . .
Penna-New JerseyMaryland.
Power Authority of
the State of New
York.
Public Service Co. of
New Hampshire.
Rochester Gas &
Electric Co.
The United Illuminating Co.
,...........
,...........
X
X
X
X
X
X
X
,...........
X
............
X
............
X
X
............
1
j
. . . . . . . . . . . . ..............
.
‘X
X
X
. . . . . . . . . . . . ..............
. . . ..............
. . . .
4
. . . . . . . . . . . . ..............
.
.
.._...........
.
.
X
Southeast Region
Summary.
9 systems.
_.__....... .
I31 steam plants
have units
which can reject load and
hold auxiliaries. 7 separate automatically and
74 are separated manually.
13 hydro and 30 steam plants
can be started without
system.
power from
West Central R
Commonwealth
Edison Co.
Eastern Wiscon:
Utilities.
Upper Peninsul
Systems.
Iowa Pool
East Central Region
American Electric
Power System.
Allegheny Power
System.
cindnnati Gas &
Elec.
Columbus & Southern Ohio Electric
Company.
Consumers Power Cc
DetmitEdisonCo...
Detroit Public Light
ing Comm.
Duquesne Light Co.
East Kentucky Rura
Electric Coop.
Indianapolis Power (
Light Co.
142
X
...........
X
...........
Industrial
plants.
...........
X
...........
........... .
. ...........
X
..............
...........
........... .
. ...........
X
..............
...........
X
X
X
X
...........
..........
X
Industrial
plants.
...........
...........
..........
...........
........... . .
X
.
.
.
X
.
X
Nebraska Syste
U.S. Bureau of
Reclamation.
Missouri Basin
tern Group.
Upper Mississi]
Power Pool.
. . . . . . . . . . . ..............
.
.
.
.
Continued
Kentucky Utilitic
co.
Lansing Board 01
Water and Lig
Louisville Gas &
Electric.
Northern Indian
Public Service
Ohio Edison
Company.
Pennsylvania PO
co.
Owensboro
Municipal Uti
Public Service
Company of
Indiana.
Southern Indiar
Gas & Electric
The Toledo Edi
co.
.
.
X
South Central
.,
X
..............
X
..............
. .
.
..............
X
Central Kansa
Power Co.
Public Service
Oklahoma.
Kansas Gas 8z
tric Co.
is
TABLE A-7.-Practices
fw rapid r&oration of service in the event of total loss of system power or when such loss of system flower is
imminent-Continued
Means of Obtaining Emergency Startup Power
--
System or Pool
team
s for
uting
- I - - - -
l East Central Region’ Continued
Kentucky Utilities
co.
Lansing Board of
Water and Light.
Louisville Gas &
Electric.
Northern Indiana
‘Public Service Co.
Ohio Edison
Company.
Pennsylvania Power
co.
Owensboro
Municipal Util.
Public Service
Company of
Indiana.
Southern Indiana
Gas & Electric Co.
The Toledo Edison
co.
-
-
-7
I nterconnecttions with
C nher systems
- -
ow&lt-2dro
. ............
X
. ............
X
.. ............
X
.. ............
X
Gasoline or
Diesel Engine:
. . .
..
.
.
.
separating Stean
Unit from System
with Auxiliaries
‘
Gas Turbinesi
i
-
-
--
...........
.
.
.............
...........
.
.
.............
.............
Available in
1968.
X
.. .......
...........
.
.
.............
X
.......
. . ..*....
...........
.
.
.............
.. ............
.......
. ............
.......
.. ............
.......
X
.......
t*
. . . .
.
.
.
.
.............
. .. .. .
............
.
itoring Steam
n Boilers for
luick Starting
-
.
.
.
.
.
X
X
.............
X
.............
.
X
X
............. ..
X
Available in
1968.
...........
. . . . . . . . . . . .. .
X
. . . . . . . . . . . .. .
X
.
.
.
West Central Region
Commonwealth
Edison Co.
Eastern Wisconsin
Utilities.
Upper Peninsula
Systems.
owa Pool . . . .
Nebraska System. . .
U.S. Bureau of
Reclamation.
Missouri Basin System Group.
Upper Mississippi
Power Pool.
X
. ............
X
. . . .
.
.
............
.......
X
X
X
............
.......
X
X
Will be operational by
mid-1967.
............. . .
...........
X
............
. .
USBR has only hydro and there is no problem restarting generatic ,n.
............
X
X
X
X
X
South Central Region
Central Kansas
Power co.
Public Service Co. 01
Oklahoma.
Kansas Gas & Electric Co.
............
.
......
X
.......
............ .
............
.
......
X
.......
............ ...
............
. .
......
.......
............ ...
To be installed.
143
TABLE A-7.-Pm&es
for rapid restoration of service in the event of total loss of system gown or when such loss of system fiower is
imminent--Continued
Means of Obtaining Emergency Startup Power
System or Pool
interconnecttions with
Ither systems
“w;~~;~o
Gasoline or
Diesel Engines Gas Turbines
-
Separating Stean1 s#toring Steam
Unit from Systen1 i n Boilers for
with Auxiliaries cBuick Starting
- -
X
...............
X
c . . . . . . . . .
X
spare capacity of system and proper maintenance assure rapid restoration of service.
,............
.............
X
X
...........................
St. Joseph Light &
Power Co.
.............
...........................
Gulf States Utilities.
South Texas Interconnected System.
City Power & Light,
Independence,
Missouri.
Western Farmers
Electric Coop.
City Utilities of
Springfield,
Miiouri.
Southwestern Power
Adm.
Southwestern Elec.
Power Co.
Board of Public
Utilities, Kansas
City.
The Kansas Gas &
Electric Co.
Texas Electric
Service Co.
Texas Power &
Light Co.
Dallas Power &
Light Co.
Central Louisiana
Electric Co.
Oklahoma Gas &
Electric Co.
Kansas City Power
& Light Co.
X
.............
144
System or :
West Rcg1
South Central RsgionContinued
West Texas Utilities
co.
Middle South System
Empire District
Electric Co.
City of Denton,
Texas.
Missouri Utilities Co
TABLE A-7.-
x
x
..............
..............
.............
. .............
Available in
1967.
,............
..............
.............
..............
..............
...........................
Being installed.
Being studied.
............ . ...........................
.............
............. ...........................
Being ordered,
X
............
X
Use old unit a
Edmond St.
Station.
..............
X
.............
All hydro system and there is no problem starting hydro.
X
Planned for
future.
...........................
[mplementing
plans.
_._.......... Understudy.. . . . . . . .
Each system has the capability of orderly and safe shutdown of units and providing for fast startup.
,.............
. . . . .
X
Being planned,
...............
Adequate facilities available. .
...............
’
. ..............
X
x
Bonneville PO\
Adm.:
U.S. corps 1
Engineers.
U.S. Bureau
Reclamati
Public Utility
trict #l Che
City of Eugen
Public Utility
#l Grant Cl
Idaho Power
Montana Pov
Pacific Power
Light Co.
Portland Gen
Elec. Co.
Puget Sound
& Light Cc
Seattle Dept.
Lighting.
‘~‘acoma Pub
Utilities.
Utah Power’
co.
Washington
Power Co.
Dept. of Wa
Power, L.1
Pacific Gas 8
tric Co.
U.S. Bureau
lamation 1
San Diego C
Electric C
Sierra PaciE
co.
Sacrament0
util. Diit.
Southern C
Edison Cc
Arizona Pu
ice Co.
Arizona PO
Authority
Tuscan Ga!
Electric (
U.S. Bur. I
mation R
Means of Obtaining Emergency Startup Power
System or Pool
Interconncc tt i o n s wit11
other systenIs
<separating Stear
Gasoline or
Diesel Engines Gas Turbines iUnit from Syster
Ow&aYro
I
--
I
with Auxiliario
.-
West Region
bnneville Power
Adm. :
U.S. corps of
EngineaS.
U.S. Bureau of
Reclamation.
Public Utility District#l chelanco.
=ity of Eugene, Ore.
Public Utility District
#l Grant Co.
[dahoPowerCo.....
tiontana Power Co.
Pacific Power &
Light Co.
Portland General
Elec. Co.
Puget Sound Power
& Light Co.
Seattle Dept. of
Lighting.
l’acoma Public
Utilities.
Utah Power & Light
co.
Nashington Water
Power Co.
Dept. of Water &
Power, L.A.
Pacific Gas & Electric Co.
U.S. Bureau of Reclamation Region 2.
Ian Diego Gas &
Electric co.
Sierra Pacific Power
co.
Sacramento Munic.
Util. Dist.
southern California
Edison Co.
4rizona Public Service Co.
4rizona Power
Authority.
Tuscan Gas &
Electric Co.
U.S. Bur. Reclamation Reg. 3.
...........
. .
I
x .........
. .
...........
.
. . .
. .
. . .
x. . . . . . . . . .
...........
I
All hydro system, one plant with separate hydro station unit.
x .........
...........
ii:::::::::
All hydro system and plants self-starting.
X:::::::::::I.x:::::::::::/:::::::::::::l:::::::::::::::
x ......................................................
x ......................................................
........................................................
x ......................................................
. .
All plants have separate units or other type power for startup.
I
I
I
All plants self-starting.
...........
. .
After present work is completed, all plants will be self-sufBcient.
x .........
. .
x. . . . . . . i. . . . . . . . I::::::::::::::‘
::::::::::::::
...........
All but two plan ts are self-starting. Planning to make these two self-starting.
x ........................ .I .............. /. ..............
. . . . . . . . . . . . . . ............. Have house turbine generators.
........... .
........... ,
All hydro, no external source of power required.
.......... x . . . . . .. . . . . . . . . . .
...........
x . . . . . . . . . . . . . . . . . . . . . . . . x........... . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.x. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
........... .
Have a 70 Mw unit with 7.3 Mw house turbine.
. . . . . . . . . . . . . .K . . . . . . . . .
X .........
. . .
IX. . . . . . . .
.
USBR-hydro
X........
TABLE
A-7.-Practices for rapid restoration.of service in the event
of
total loss of system power or when such loss of system power is
imminent-Continued
T
System or Pool
Means of Obtaining Emergency Startup Power
-
Interconnect.
tions w i t h
other systems
Gasoline ad
Diesel Engin es
1
--
--
Separating Stearn Storing Steam
Unit from Syster n in Boilers for
with Auxiliarie! s 1Quick Starting
- -
Gas Turbines
-
--
Area pool
-
Norfkasf regio;
Niagara Mc
Corp.
West Region-Con.
Nevada Power Co.. .
Salt River Project.
City of Colorado
Springs.
Colorado Ute Electric Assn.
Public Serv. Co. of
Colorado.
Southern Colorado
Power Co.
U.S. Bureau of Reclamation, Reg. 4.
U.S. Bureau of Reclamation, Reg. 6.
U.S. Bureau of Reclamation, Reg. 7.
El Paso Electric Co.
Public Service Co. of
New Mexico.
Community Public
Service Co.
Plains Elec. Gen. &
Trans. Coop.
U.S. Bur. of Reclamation, Reg. 5.
.
X
X
X
X
X
...........
X
..........
X
X
..
.
..
.
Planned. . .
X
...........
............ . . . . . . . . . . . . . .
New York !
&GasCc
. . . .
............
Central Hu
Electric (
...............
CONVEX
Emergency procedure manual-New Mexico Power Pool.
.
-
I
e. Practices and Plans for Use of Digital
Computers
The electric utility industry has used computers
for many years in planning the operation and expansion of generating and transmission facilities.
Until recently, these have been analog devices, but
the digital computer and its associated technology
has developed in about the last ten years to the point
that it has replaced the analog computer in many
instances, and its use is increasing rapidly throughout the industry. Practically all utilities can now use
digital computers to some extent in making system
expansion and operation studies, and many have
special purpose machines for economic dispatch
determination and control. Still others utilize computers to monitor operation and in some instances
control the start-up and shut-down of turbogenerators.
146
............ . . . . . . . . . . . . . . .
X
All hydro, no external source required.
:.
.....
.
............ ...............
X
. . . . . . . . . ., . . . ............ ...............
. . . . . . . . . . . . . ............ ...............
I
I
-
This section of the report, however is concerned
primarily with the use of digital computers on a
real-time basis for implementing various phases of
power system operation and control.
The survey results show that ten major utility
systems had real-time computers in use primarily
for economic dispatch computations and to direct
analog load-frequency control equipment. There
were 24 control computers on order, being installed,
or definitely planned. Three of these were primarily
to perform economic dispatch and load-frequency
control, five were to be used for system security
monitoring, and sixteen were to perform all of these
functions.
The following tabulation summarizes the responses to the Regional Advisory Committees’
inquiries concerning plans and practices for these
types of application.
New Engla
System.
Consolidat
pany of I
-
TABLE A-8.-Practices and plans
Area pool or system
Computer
type
--
for use
of digital computers
Present uses
Northeast region:
Niagara Mohawk Power
t
Corp.
I
1!n service.. . . . .
On line
digital.
Yew York State Electric
& Gas Corp.
Dnorder......
On line
digital.
Central Hudson Gas &
Electric Corporation.
Under consideration.
Data
logging.
CONVEX . . . . . . . . . .
Planned.
.
On line
digital.
New England Electric
System.
Consolidated Edison Con
pany of New York.
Planned. . . . . .
On line
digital.
On line
digital.
In
.
service.
/
.
Economic
dispatch.
..............
Economic dispatch and sys
tern security.
I
Future uses
Economic dispatch will absorb a very small
part of the capability of the computer.
Plans are being developed to use the
computer to provide guidance and instructions for system operation under both
normal and emergency conditions. N.Y.
State Electric & Gas Corporation has
ordered a digital computer and both
computers will be so designed and operated that they will provide maximum
mutual benefits.
Engineering applications and for expansion
of the operations center. The computer
will be designed and operated so it will
provide maximum mutual benefits with
Niagara Mohawk’s computer.
Provide printout of the occurrence of
breaker operations and alarm conditions
on the bulk power supply system. The
system will provide more detailed load
and voltage data and reduce transmission
interruption time by providing faster
intelligence and a rapid summary of
equipment out of service.
Will back up load frequency control. Will
display power flows at more tie points
and more generating stations than
presently available to dispatcher. System
data will be available on call from the
computer which will permit the dispatcher
to locate trouble areas and to take
remedial action.
The computer will be programed to make
security checks of spinning reserves and
the status of lines and capacity in specific
areas. Decisions on the number and how
such checks will be made is under
consideration.
Same as above.
At present, the computer periodically
compares tie feeder and line loading with
the ratings and signals operator if loads
approach or exceed the ratings. It will
be possible to determine the effects of tie
fee&r and generator outages on the
security of the system. The system
security check is being programmed to
make an analysis of the situation followed
by a printout of methods to correct any
impending or existing abnormal conditions.
The computer checks spinning reserves on
demand and is being programmed to
predetermine the safe and economical
allocation of spinning reserves.
_.:
‘1.
I
TABLE
Areapoolorsystem
A-8.-Practices and plans for use of digital computers-Continued
-
-
Ex cted date
0r
operation
Computer
type
-
-
Future uses
Present uses
--
--
Northeast region-
.Mortheast region-Con.
Ccnsolidated Edison Company of New YorkContinued
Long Island Lighting
Company.
On order. .
t
Online.....
Initially. . . . . .
1. Automatic
load frequency control.
2. Economic
dispatch.
3. Logging.
Programs for the allocation of MVAR’s on
Edison’s system are under study.
Security checks, spinning reserve allocation and MVAR scheduling can be extended to cover not only Edison’s
system but also the pool operation.
The following functions are under study:
1. Automatic control to determine need
for capacity and automatically send
start signals to quick-starting peaking
units.
2. Automatic transmission security review
for frequency, voltage or load abnormalities with an initial alarm and with
the ultimate goal of automatic “make
safe” signal via supervisory.
3. Review frequency decay, tie line conditions and initially to alarm for these
conditions. The ultimate goal is to send
enabling signal to supervisory controlled
frequency relays to shed required load.
4. To improve rate of response of generating
units. Telemeter data on steam pressure, drum level, etc. may be monitored. This will enable the computer to
initiate rapid load changes in times of
emergency without endangering the
Units.
Pennsylvania-New
Jersey-Maryland
Interconnection
148
Area pool or
1967.........
.
.
On line
digital
. . . . . . . . .
5. All of these systems under study are ultimately closed loop systems and a great
deal of attention must be given to assure
that the systems are fail safe.
Specific application areas in the initial
operation are:
1. Master Schedule-determine the mix of
steam, hydro, pumped storage, gas turbine, and diesel units to provide the optimum schedule.
Outage
Scheduling2. Transmission
through remote console, each system has
access to computer to simulate any contemplated transmission changes for
maintenance. If the outage is scheduled,
the system configuration would be
changed within the computer for the appropriate period and subsequent evaluations would be made reflecting the effects
of all scheduled outages.
Pennsylvania-N
Maryland In
tion-Contin
TABLE A-&-Practices
Area pool or system
.Northeast region--Con.
Pennsylvania-New Jersey
Maryland Interconnec
tion-Continued
Rx cted date
0%
operation
and plansjor USC of digital computers-Continued
-
Computer
type
Present uses
Future uses
-3. Megawatt Monitor-the power flow on
selected lines within and between PJM
systems and between PJM and neighboring pools will be monitored to determine if any area has reached a limiting
value of interchange due to equipment
rating or stability. When a limiting condition is found to exist, information to
this effect will be printed at the appropriate dispatch center as well as at PJM
dispatch center.
4. Control Area Regulation-PJM functions as a single control area and the
control signals sent to the individual
system’s Automatic Dispatch System
equipment will be developed by the
computer.
5. Dispatch Lambda-the computer will
develop more comprehensive incremental transmission loss. Scaled values of
Lambda will be sent to each system’s
ADS approximately every five minutes
and will result in the system’s generation being dispatched more economically.
6. Pool-to-Pool Scheduling-PJM is interconnected with four neighboring pools
and the computer will develop the PJM
cost and replacement values used in establishing an hourly interchange schedule with each pool.
7. System Security-this program is initiated when one or more of the PJM
frequencies decay to 59.75 cycles per
second. Messages will be printed in the
PJM office and on the system’s remote
console describing the abnormal condition and possible corrective measures.
8. Data Logging and Reports-the teleprocessing capability of the computer
and data transmission system makes it
suited to take on the additional task of
data collection from remotes, data checking, data storing, and data distribution
and logging at selected terminals. The
data handled relates to Present Condition (unit and transmission line status)
Scheduling Conditions (estimated loads
and start-stop schedules), Summary Reports (periodic summaries of operating
experience and production cost).
9. Accounting-determine the division of
savings and preparation of monthly
billing statements of energy and capacityinterchanged.
149
f. lnterrupm
Support
TABLE A-a.---Practices and plans for use of digital computers-Continued
Area pool or system
-.
-
-
Expected date
of operation
--
Computer
We
-
Future uses
Present uses
-_
Data logging
and monitoring.
East Central region:
summary.
Several in use.
On line
digital.
West Central region:
..............
None in use fo r coordination of
information or system control.
Summary.
Southeast region:
summary.
South Central region:
summary.
One in service.
On line
digital,
Three being
planned.
On line
digital.
Some in service.
On line
digital.
Some being
planned.
West region:
summary. . . . . . . . . . . . .
150
Four in service.
On line
digital.
Iwo on order,
others are
being considered by 12
utilities.
On line
digital.
Following
tion, it was
in an atten
Consequeni
connection:
mental thal
A wide s
attention 0
turbance, 1:
--
Load frequency
control and
economic
dispatch.
Load frequency
control and
economic
dispatch.
Load frequency
control.
Economic
dispatch.
While none of the systems in this region is
now using a digital computer for system
security checking or directly controlling
stability or reliability, much attention is
being given these matters.
Plans are not far enough along to disclose
more than generalities. It will be a year
or more before any actions are taken.
Systems are actively evaluating the need
for such facilities, both from the point of
view of expanding computer facilities in
existing control centers and planning for
future operational coordination on an interpool basis. None, however, are expected to be operational within a year or so.
Two of these planned installations will have
security monitoring functions.
tions assist
receive no 1
In order
perspective
stapces of c
I
Area regulation.
Selective load shedding.
Generation and transmission control for
economic dispatch and area regulation.
1
Load Frequency
control.
Economic dispatch.
Data collection.
One utility has ordered seven digital computers to be installed at modern substations for annunciation and time sequence monitoring. The data from
these units will be made available to the
system drspatcher by way of a new
central dispatch computer.
One utility has hired a consultant to study
the operating systems and to evaluate the
current status of automatic control
and data management systems with rcspect to their adequacy.
Computers are being studied for system
security and supervisory control.
26%:
f. Interruptions Avoided lhrough Interconnection
Support
Following the November 9,1965 power interruption, it was recognized that some systems collapsed
in an attempt to restore service to their neighbors.
Consequently, there were suggestions that interconnections between systems might be more detrimental than helpful.
A wide spread power interruption comes to the
attention of everyone within the area of the disturbance, but the instances in which interconnections assist in preventing an interruption usually
receive no publicity.
In order to put interconnections into their proper
perspective, it seemed advisable to document instapces of disturbances which probably would have
caused interruptions on the affected system except
for the assistance rendered through interconnections. Accordingly, the Commission’s Regional Advisory Committees assembled some information of
this nature.
Brief summaries of the reports from the six Regions appear in Chapter 3 of this report. It is
always difficult to assess the extent of the disturbance which would have occurred if existing interconnections had not been present, but several of
the cases reported point conclusively to the value
of strong interconnections for improving power
supply reliability. Additional information on the
value of interconnections may be found in Chapter
II of Volume II, Advisory Committee Report on
Reliability of Bulk Power Supply.
APPENDIX B
MODIFICATIONS IN NORTHEAST POWER SYSTEMS SINCE
NOVEMBER 9, .1%5
I Introduction
During the calendar year following the Northeast
interruption, ‘the affected major utilities invested $20 million in new facilities and improvements to protect existing facilities and to prevent a
recurrence of a cascading power systems failure.
An additional $30 million has been committed for
further improvements that are being made as
rapidly as procurement and installation schedules
will permit.
This Appendix lists some of the major improvements that have been made on the Northeast systems. Tabular summaries with a minimum of textual material are provided for those areas of improvement that are discussed in Appendix A. For
other types of improvement, representative samples
are used to indicate what has been done. In both
cases, the information shown is considered typical
but does not necessarily provide complete coverage
of all system improvements that have been made.
It rather demonstrates the general direction that
system improvement work has taken as a result of
the knowledge that was gained from the blackout
experience.
power
Relaying
Power system protection is a highly specialized
field. Its purpose is to automatically monitor system
behavior or performance and to either give warning or initiate action when predetermined limits
of voltage, current or frequency are reached or
exceeded. Protective actions involve isolation of
damaged or malfunctioning parts of the system; adjustments in generation or load to meet emergency
conditions; and the mechanical and electrical protection of equipment during the shut-down process
if loss of service cannot be avoided. Various types
of relays provide much of the automatic monitoring
and action-initiating service that is so essential to
system protection.
Following the determination of the cause of the
November 9 failure, utility systems throughout the
area initiated reexamination of their relay applications and settings to assure their adequacy for present and immediate future conditions.
The first step, taken by the Hydra-Electric Power
Commission of Ontario, was to block out the backup relays (on the five lines out of the Sir Adam
Beck No. 2 Station) that had operated to initiate
the November 9 disturbance. The next step was to
install additional relays which give the lines two
zones of protection and increase their load-carrying capability. Blinder relays have been ordered and
will soon be installed to replace the interim installation described above. These blinder relays are
designed to limit their action to a narrow’beam
that parallels and encompasses only the lines out of
the Beck plant, with down-system protection relegated to other protective installations.
Ontario has been coordinating its studies with
those of the Niagara Mohawk Power Corporation
and the Power Authority of the State of New York
in the investigation of relay systems which would
protect against massive power surges into either the
United States or Canada. As a result of these studies,
an interim installation of overcurrent power directional relays was made, within about 10 days after
the November 9 power interruption, at Niagara
Mohawk’s Packard Station and at PASNY’s
Niagara switchyard on the 230 kilovolt tie-lines to
Ontario Hydro. The relay control scheme requires
manual adjustment for varying power flows toward
Ontario. If a rapid reversal in power flows toward
New York should occur and exceed predetermined
limits, the relays will initiate the opening of the
Niagara tie-line power circuit breakers to prevent a
widespread disturbance. Ontario has also installed
interim relays on the 230-kilovolt lines, set to operate if there is a significant rate of change of power
flow into Canada. Since the direction of flow is normally into Canada, the rate of change appears to
153
be a better guide to protection than the amount of
power flow. Ontario is installing automatic relays
which will provide the same protection as the interim installation but the relay settings will be automatic. To complete the protection, a tmnsfer trip
circuit has Ibeen installed which will act to simultaneously trip selected generating units in the
Saunders Hydroelectric Plant on the St. Lawrence
River if the ties at Niagara trip out.
Typical of other actions with respect to protective
equipment are those taken by Central Hudson Gas
and Electric Company. The protective levels and
margins previously determined desirable for relay
settings were re-examined on all the Company’s
transmission lines. All the protective devices on the
system were field tested at least once between November 9, 1965 and February 1, 1966. The field
testing included actual test tripping of all circuit
breakers actuated by these relays. Modifications
were made to the relaying and control wiring of
the Danskammer Steam Station units so as to keep
the generator auxiliary load connected to each unit
if the unit is automatically tripped from the system.
This makes possible continued operation of the
turbine generators over an extended period, in readiness to pick up load as required. Conducted tests
proved the feasibility of this type of operation.
Every. utility in the Northeast has reviewed the
adequacy of its protective equipment, and hundreds
of modifications or additions have been made to
provide optimum protection under all foreseeable
conditions, including those studied in detail as a
part of the stability analyses described in Volume
III of this Report.
Emergency Power at Generating Stations
Appendix A explained why emergency power is
critical at generating stations and other system key
locations to provide lights, communications, telecommunication and telemetering, to drive recording charts and to provide other essential functions
in case of loss of system service. Because of its extreme importance and the difficulties encountered
as a result of lack of emergency service during the
power interruption, all utilities in the Northeast
gave immediate and special attention to this need
and instituted a program of modifications and improvements as necessary. These endeavors involve
many types of improvements, depending upon operating conditions within each utility or pool. Table
El summarizes major improvements that have been
made at generating stations in the Northeast that
have capacities of 100,000 kilowatts or mom. These
154
stations represent nearly 90 percent of the total capability of the systems involved. There is no particular
significance to the arbitrarily selected 100,000 kilowatt limit for unit size covered by the table except
that it provides information to demonstrate that a
reasonable portion of the system capability is protected during rundown and can be restarted with a
minimum of delay.
Communications, Instrumentation, and
Data Transmission
Uninterrupted communications within a utility
system and with interconnected neighboring utilities are critical to service reliability. Communications include both voice and signal transmission,
involving ordinary short-wave radio, microwave
systems, metallic circuit transmission such as company-owned private lines and Bell system telephone
circuits, and carrier-current systems using power
transmission lines or insulated shield wires on conventional transmission lines. All require electric
power for signal propagation and transmission; thus
it is extremely important that adequate auxiliary
or back-up power is available at dispatching offices
and service centers to insure that both voice communication and recording equipment will operate
continuously through emergency periods.
Communications and instrumentation go handin-hand. The system dispatcher must rely on data
transmitted from instrumentation at remote locations for much of his knowledge of minute-to-minute operating conditions on his system. As automation and computerization progress, reliance on
transmitted data from remotely instrumented locations becomes extremely critical.
Power system instrumentation is designed also
to provide a continuing record of all system conditions, including rapidly changing transients, to
permit analysis and reconstruction of what transpires during emergency periods such as those of
November 9,1965.
Shortcomings or deficiencies noted at the time of
the area-wide disturbance included loss of ringing
power and signal lights on land line voice circuits,
loss of power to drive teletype printers, loss of signal fidelity (accuracy) in telemetered data, insufficient power or lack of back-up for radio and
microwave systems, and insufficiency of telephone
circuits between dispatchers and plant operators or
between dispatch centers on different systems.’
Perhaps one of the more critical deficiencies
occurring during the time systems were breaking up
on November 9 was lack of a true and complete
record of SYE
and indicati
dual-range t
in all cases a
the instrume
scale. Also, :
drive slowed
dication of tl
In some ins
curred both
per second
was difficul
Oscillograpl
for “after th
out of photc
sent the corn
Many im
munication
with major
tive channe
operating tl
significant (
table B-2.
Spinning
When th
night of No
state New ‘I
reserve coul
material ass
the Eastern
spinning re
been expec
normal con
separated f:
not occur, 1
gation of r
conducted I
System Stu
September
Report. )
Prior to
area was ld
generation.
ing supplie
in the systr
1474 megai
percent of
in the iirsl
creased by
ating an ef
additional
record of system frequency fluctuations. Recording
and indicating frequency meters were generally of
, dual-range type and operating personnel were not
in all cases able to immediately determine whether
the instrument was on the compressed or expanded
scale. Also, as system frequency decayed, the chart
drive slowed down and thus gave an erroneous indication of the duration of low frequency operation.
In some instances, wide frequency deviations occurred both above and below the normal 60 cycles
per second in such a short period of time that it
was difficult to determine which occurred first.
Oscillograph records were in some cases deficient
for “after the fact” analysis because instruments ran
out of photo-sensitive paper and thus failed to present the complete picture.
Many improvements have been made in communication systems since the power interruption,
with major emphasis placed on providing alternative channels and independent power sources for
operating the communication facilities. The more
significant of these changes am summarized in
table B-2.
Spinning Reserve
When the initial disturbance occurred on the
night of November 9, 1965, the break-up in the up
state New York area came so quickly that spinning
reserve could not respond rapidly enough to be of
material assistance in preserving system stability. In
the Eastern New York-New England area, however,
spinning reserve in service would normally have
been expected to enable the area’s recovery to a
normal condition of frequency and voltage after it
reparated from the western systems. Since this did
not occur, the Commission urged intensive investigation of reserve levels and response. This study,
:onducted by the Eastern New York-New England
System Studies Group, is covered in their report of
September 15, 1966. (See Volume III of this
Report.)
Prior to the disturbance the load in the “island”
irea was 14,678 megawatts with 13,204 megawatts
pmeration. The balance (1474 megawatts) was being supplied from external sources. When the split
in the system occurred, resulting in the loss of this
1474 megawatts of capacity, 1046 megawatts, or 71.0
percent of the loss was picked up from reserve units
In the first 30 seconds. However, losses were in:reased by approximately 175 megawatts, thus cresting an effective deficiency of 1649 megawatts. An
additional 40 megawatts was picked up in the next
30 seconds, resulting in a total pick-up in one minute
of 1086 megawatts, or 73.7 percent of the loss of
capacity and 7.4 percent of the area load. The maximum non-coincidental pick-up in the period 5: 16
pm to 5: 19 pm was 1260 megawatts, or 87.0 percent
of the capacity originally lost. However, in holding
the interconnected systems together, it is the coincident pick-up that is especially important, and the
total coincident pick-up was 1086 megawatts, only
66.7 percent of the 1626 megawatts of spinning reserve thought to be available. This experience illustrates the significance of rapid response of reserve
capacities, and provides a basis for evaluating the
information presented in table B-3.
The criteria and practices with regard to maintenance of spinning reserve vary among the several
groupings of Northeast electric utility systems.
Merging of power pools such as the recent fonnation of a single pool among the seven principal utilities of New York and the establishment of the
NPCC are likely to bring about some modification of
the practices in effect at the present time. Generally,
however, the operating utilities consider present
practices, outlined in appendix A, to be reasonable
and adequate, and no significant changes in reserve
policies are planned.
Table B-3 summarizes 1966 spinning reserve data
for the systems directly affected by the November 9
disturbance.
load Reduction
At the time of the Northeast interruption, no
CANUSE system employed automatic load shedding. This is in marked contrast to the situation in
some other parts of the United States where it is employed to a considerable degree. (See appendix A)
The Spinning Reserve Task Force of the Eastern
New York-New England Systems Studies Group
concluded that “the spinning reserve policies now
in effect provide for adequate spinning reserve. An
extreme disturbance, however, may result in separations of the system. Under these conditions, the reserve may not be sufficient in all areas or cannot be
picked up fast enough to restore frequency. Therefore, provisions for load shedding should be initiated
by automatic and/or manual means quickly enough
to prevent further deterioration of frequency and
voltage. If this cannot be accomplished, further separation of systems or areas should be considered.”
In February 1966, the Eastern New York-New
England (ENY-NE) System Studies Group appointed a Station Operation Task Force to investi155
T ABLE B-l .-Emergency Pawn Su@lies-Generating
System and Station
Generating Stations
100,008 kw and over
Type
Boston Edison Co.:
Edgar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
L street. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mystic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Steam. . . . . . . . .
. . ..do . . . . . . . .
. . . . do . . . . . . . .
NewBoston . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Central Hudson Gas and .Electric
Corp.-Danskammer .
Rundown Auxiliaries Added
since 11/9,65
Size-kw
Stations with (
Rel
Capacity kw
Diesel. . . . . . . . .
..............
Diesel. . . . . . . . .
150
............
150
...........
...........
.... .......
. . . . do . . . . . . . .
. . . . do . . . . . . . .
150
..........
. . . . do . . . . . . . .
..............
............
...........
457,860
225,750
618,750
Central Maine Power Co.:
Mason . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
W.F.Wyman . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
146,500
213,636
Diesel. . , . . , . . ,
108
Consolidated Edison Co.:
ArthurKill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Astcmia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
EastRiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
59thstrcct . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
HellGate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
IndianPoint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
HudsonAvenue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . do. . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
Nuclear. . . . . . .
Steam .........
376,200
1,530,600
833,652
149,500
646,250
275,000
845,000
. . ..do . . . . . . . .
. . ..do. . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
............
............
1, 200
............
600
............
............
KentA+enue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Ravenswood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
74thStreet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ShermanCr . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Waterside . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
.... do . . . . . . . .
. . . . do . . . . . . . .
. . . . do. . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
107,500
1,827, 700
269,000
216,500
712,250
. . ..do . . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
..............
............
. ...........
. ...........
. ...........
. ...........
Eastern Utilities Associates-Somerset. . . . . . . . . . . . . . . .
. . ..do . . . . . . . .
325,ooO
..............
. ...........
Holyoke Water Power Co.-Mt. Tom. . . . . . . . . . . . . . . .
. . . . do . . . . . . . .
136,060
. . . . . . . . . . . . . . ............
Long Island Lighting Co.:
E.F.Barrett . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
FarRockaway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Glenwood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PortJelIerson . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . do . . . . . . . .
. . . . do . . . . . . . .
. . ..do . . . . . . . .
. . . . do . . . . . . . .
375,000
147,236
397,272
467, ooo
..............
..............
..............
..............
. ...........
............
............
............
Diesel. . . . . . . . .
..............
- - 4al
............
. . . ..*........ . . . . . . . . . . . .
Units at ea
varying fi
600 kw e;
units hav
since 1 l/Z
24 diesel
10,200 kv
All units p:
auxiliaric
1965.
New England Electric System:
Comerford . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
S.C.Moore.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hydro . . . . . . . .
Brayton Point. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SalemHarhor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Steam. . . . . . . . .
. . ..do. . . . . . . .
482, 040
319,938
..............
..............
............
............
..........
..........
Manchester . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
slnlthstret . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. . . . do . . . . . . . .
. . ..do . . . . . . . .
147,000
206,625
..............
..............
............
............
_..._.....
Diesel. . . . . . . . .
100
New England Gas and Electric Association-Cannon St. .
156
. . ..do . . . . . . . .
. . ..do . . . . . . . .
St&ions with ca@ci~ of 100 megawatts or mOr6
1Restart Service Added or Improved
Since 1 l/9,65
-
Remarks
-
Type
-
-.
spacity kw
........................ . ..................
.......................I Gas Turbine. . . . . . .
.......................! isolated Unit. . . . . . .
...........
18,594
50, ooo
. . . . . . . . . . . . . . . . . . . . . . . . . ..................
...........
. . . . . . . . . . . . . . . . . . . . . . . . 1Diesel. . . . . . . . . . . . .
5,500
. 1Hydro . . . . . . . . . . . .
. . . . . do . . . . . . . . . . . .
Units at each station
varying from 150 to
600 kw each. Fourteen
units have been added
since 1 l/9/65. Total of
24 diesel units provide
10,200 kw.
...........
...........
Gas Turbine. . . . . . .
Isolated Unit . . . . . . .
,Gas Turbine (2)r. . .
16,000
7,500
34,204
,GasTurbine . . . . . .
(Stored Steam to start
Gas Turbine (2)r.
Turbine (2)r. ..
IGasTurbine...... .
IGas Turbine ($1. ..
‘
Stored Steam. . . . .
IGasTurbiner...... .
IGas
.
Isolated Unit.. . . .,.
.
IHydra
.
............
Remarks
16,575
7, 500 unit
35,696
29, 600
16,000
37,188
..........
16,575
Fuel oil pump converted to DC operation.
Relaying installed to isolate #3 unit to provide start-up
for station and system.
Also can be direct-connected to Sturgeon Pool and
Never-sink Hydro plants.
Generator aux. load direct-connected to each unit to
permit no-load operation.
Restart power available, with emergency switching, from
system hydro stations.
Restart units can be switched to any unit. All rundown
equipment starts automatically. Some house generators
wired to carry some auxiliaries. Start-up power at some
stations provided by nearby steam-heating plants. Unit
isolation under study. Ravenswood plant has steamdriven oil pumps, as well as battery-cranked diesel
auxiliaries. All stations can be restarted without system
service. Switching arrangements to isolate units at
59th St., 74th St., and Waterside.
. . . . . . . . . . . . One small unit in plant can be isolated and connected
to low-voltage bus to provide cranking power for other
units.
. . . . . . . . . . . . Restart power provided by direct line to Cabot hydro
station.
Turbine. . . . . . .
. . . . do . . . . . . . . . . . .
. . . . do . . . . . . . . . . . .
. . . . do . . . . . . . . . . . .
(ks
All units provided with
auxiharies on Nov. 9,
1965.
18, 600
15,000
16, 000
15,009
...........
. .
........................ 1Diesel (4). . . . . . . . .
........................ . . . . d o . . . . . . . . . . .
11,000
10,000
Diesel . . . . . . . . . . .
. . .da . . . . . . . . . . .
2,750
2,750
Stored steam. . . . . .
..........
....................... .
....................... .
.
All units equipped with dc backup oil pumps. Gas turbine
unit at Southampton station can be used for cranking
power at steam stations. Far Rockaway unit to be
isolated to insure service to New York Transit Authority
Minor changes in sta. service assume adequate oil
pressure and provide faster availability of sta. prime
movers in case of emergency.
Diesel equipment located at Gloucester, connected by
underground cable.
Roth Manchester and South St. Stas. can be fed from either
emergency generator.
Restart after short outage can be provided from stored
steam. System service required for cold restart.
T ABLE B-1.-E mergctuy Power Supplies-Generating Stations
with Capacity
-
Generating Stations
100,000 kw and over
System and Station
Rundown AuxiEariea Added
since 11/9,65
-
-
Typt
Size-kw
Tvpe
.
. . ..do . . . . . . . .
.
kw
- -
--
New York State Electric and Gas Corp. :
Goudey.......................................
ICapacity
Re
145,750
.............. . . ...........
Emergency
all statio:
. . . .do . . . . . . . .
. . ..do . . . . . . . .
160,000
270,000
.............. . . ...........
.............. . . ...........
.
. . . .do . . . . . . . .
. . . . do. . . . . . . .
. . ..do . . . . . . . .
. . ..do . . . . . . . .
376,000
Klo, 000
628,000
828,000
Diesel. . . . . . . . .
. . . .do . . . . . . . .
. . ..do . . . . . . . .
. . ..do . . . . . . . .
700
700
700
700
.
.
. . . . do . . . . . . . .
209,636
propane. . . . . . .
100
..........
......
.
.
......
.
.
......
.
.
......
.
.
.......
.
.
. . ..do . . . . . . . .
. . . . do . . . . . . . .
. . ..do . . . . . . . .
. . ..do . . . . . . . .
. . ..do . . . . . . . .
479,000
176,000
326,400
421,996
216,750
..............
..............
..............
..............
..............
...........
...........
...........
...........
...........
..........
..........
. . ........
..........
: .........
.
.
. . . . do. . . . . . . .
294,520
Stored Steam
Hydro.
Hydro . . . . . . . .
240, m
1,953,900
912,000
Hydro . . . . . . . .
. . . . do. . . . . . . .
. . . .d a . . . . . . .
Steam. . . . . . . . .
. . . .d o. . . . . . . .
113,636
190,000
..............
..............
. . . .d a . . . . . . .
. . . .d o. . . . . . . .
206,200
252,600
..............
..............
. . . .do. . . . . . . .
261,042
..............
. . ..d a . . . . . . .
. . ..d a . . . . . . .
146,250
155,500
..............
..............
Nuclear. . . . . . .
185,000
..............
Greenidge . . . . . . . . . . . . . . . . . ............
Mill&n. . . . . . . . . . . . . . . . . . . ............ . . . .
Niagara Mohawk Power Corp. :
oswego. . . . . . . . . . . . . . . . . . . .
Albany . . . . . . . . . . . . . . . . . . . .
Dunkirk. . . . . . . . . . . . . . . . . . .
C. R. Hun&y. . . . . . . . . . . . . .
............
............ . . .
............ . . . .
............ . , . .
Northeast Utilities
W. Springfield . . . . . . . . . . . . . . . . . . . . . . . .
Devon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Montville . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NorwalkHarbor . . . . . . . . . . . . . . . . . . . . . . . .
Middletown. . . . . . . . . . . . . . . . . . . . . . . . . . . .
So.Meadow...‘
.........................
Orange and Rockland Utilities, Inc.-Lovett . .
Power Authority-State of New York:
Lewiston. . . . . . . . . . . . . . . . . . . . . . . . . .
Moses Niagara . . . . . . . . . . . . . . . . . . . .
Moses Power Dam . . . . . . . . . . . . . . . . .
Public Sexvice Co. of New Hampshire:
Merrimack........................
schiller...........................
Rochester Gas and Electric Corp.:
RochesterNo.3... . . . . . . . . . . . . . . . .
Rochester No. 7. . . . . . . . . . . . . . . . . . .
Yankee Atomic Electric Co.-Rowe.. .
.
.
.
.
.
.
.
.
.
.
. .
1
.
. .
....
.
...
...
....
,.
.
.
. .
f
.
.
.
Unite-d Illuminating Co. :
Bridgeport Harbor. . . . . . . . . . . . . .
English . . . . . . . . . . . . . . . . . . . . . . . . . . .
Steel Point. . . . . . . . . . . . . . . . . . . . . . . .
.
,.
...
....
....
.
,.
.
,.
.
.
-
1 On order.
1.58
. . . . do. . . . . . . .
. . . . da . . . . . . .
.
. .
. .
. .
. .
...........
...........
..........
..........
..........
..........
1 7 5
...........
...........
...........
..........
..........
..........
...........
...........
........
........
. .
...........
...........
..........
..........
. .
...........
. .
. .
. .
. .
.
.
. .
...........
...........
. .
...........
. .
-
..........
..........
with Cajacity
of
700 megawatts or mwcContinued
-
R.estart Service Added or Improved
Since 11,/g, 65
Type
Zapacity kw
H[ydro . . . . . . . . . . . .
Stored steam
..........
....................... . . . . . . . . . . . . . . . . . . .
....................... Dhx.L . . . . . . . . . . . .
..........
....................... HJydro . . . . . . . . . . . .
....................... . ..do . . . . . . . . . . . .
....................... . . . ..d 0.. . . . . . . . . . .
. . . . ..d 0.. . . . . . . . . . .
..........
..........
..........
..........
Cranking power for steam station provided by hydro
plants, with facilities for rapid sectionalizing to provide direct line between hydro and steam plants.
New 115/35 transformer added at Albany Sta. to
provide this service. Stored steam used for restart
after short outage. Standby air pressure tanks provided
at hydro plants to open gates should normal station
service be lost.
........................ LJnit Isolation . . . . .
100,009
Start-up power also provided by direct line to Cobble
Mountain hydro station
........................ Gla9 Turbine. . . . . . .
........................ c1iesel. . . . . . . . . . . . .
........................ G)as Turbine. . . . . . .
........................ . . . ..d 0.. . . . . . . . . . .
: ....................... . . . ..d 0.. . . . . . . . . . .
15,370
5, 500
16,320
18,000
10, Otnl
........................ I-I lydro. . . . . . . . . . . . .
..........
Start-up power available from Mongaup River hydro
plants. 50 kw start-up emergency unit installed at
Mongaup.
.......................E Iydro . . . . . . . . . . . .
........................ . . . . .da . . . . . . . . . . .
........................ . . . . .do. . . . . . . . . . . .
..........
..........
..........
Generating units at each plant wired to provide station
service completely independent of any transmission system connections or normal source of station service
power.
........................ . . ... do. . . . . . . . . . . .
........................ . . . . . do. . . . . . . . . . . .
..........
..........
Stations can be started by direct service from hydro
stations.
........................ . . . ..d a . . . . . . . . . . .
........................ . . . . .da . . . . . . . . . . .
..........
..........
Beebee steam station units can be started from nearby
hydro plant, to start restoration of service in case of
system failure.
120,000
Start-up power provided to Steel Point plant by 138 kv
direct cable.
No cranking auxiliary. Tie to Bridgeport being considered.
Direct connection to emergency power supply at Bridgeport Harbor.
-Emergency generators at
all stations.
........................ cJnit isolation; jet
Stored steam arrangements available for prompt restart.
Service from hydro interconnections or Milliken station required for cold restart.
Two units, wired to both stations.
5, 500
turbine.
........................ . . . . . . . . . . . . . . . . . . .
........................ . . . . . . . . . . . . . . . . . . .
..........
..........
....................... . . . . . . . . . . . . . . . . . . . .
..........
10,000 installed in 1962.
159
T ABLE
B-2.-Communications, Instrumentation and Data TransmissionSign$icaficant System Improvements
Since Nov.
1#.5
System
Operator’s communications and aids
Recording equipment
Boston Edison Company. .
The communications system operated satisfactorily
during the November 9 emergency. The system has
been analyzed and it was concluded that no significant
changes are necessary. The leased circuit system is
backed up by radio communication equipment.
Expanded-scale frequency meters added to monitor 115
KV transmission. Two additional radio frequencies
assigned, one to be used solely for emergency, the
other for mobile equipment. Automatic voice alarm
system provided between each of the four operator’s
offices, with alarm also provided in other southeast
New York operator’s offices. Emergency communications power provided at all key stations. Direct leased
telephone lines added between control center and
Danskammer Station. Computer system under consideration.
Signal system provided to warn all station operators
when emergency exists, and also to alert system operators of neighboring utilities. Two separate leasedwire channels available to all generating stations.
Signalling is independent of system AC supply. At
energy control center, 100 KW diesel provides emergency lights, instrument drive and other emergency
service. Audible warnings and printouts of tie line
overloads are provided by computer.
Alarm system warns when inter-ties within Southeastern
New York companies become overloaded. Clearchannel radio contact available to all company
stations at all times. Emergency power provided at
operations center by 150 KW d&cl generator. Largescale indicating meter added to provide more easily
read frequency information.
Single-range meters installed. Meter drive3 at Millbury
dispatch center provided by 125 KW gasoline gcnerator and 50 KW diesel generator. Basic communications system completely operative without system
service. Ringing service now provided independently
from system service.
Leased line and carrier channels provided adequate
communications during emergency. Independent
power supply for ringing and signal lights has been
arranged for. Unlisted telephone numbers provided at
key stations. Radio system changed to dual frequency.
All operating centers (23) and dispatching centers (13)
equipped with emergency power sources.
Direct telephone communication to neighboring systems
has been provided. “Line Load Control” insures availability of needed service during emergencies. Single
range frequency meters provided at dispatch centers.
Emergency battery and AC emergency power provided
at dispatch center. Additional radio equipment provided. All visual and audible signals connected to
auxiliary power supply. Unlisted telephone numbers
provided. Stations provided with quick connections to
mobile generators. Computer provides line data and
other control information. Instructions and training
on restoration of service without normal communica-
Recording equipment is provided
with back-up power to provide
continuous record during emergency.
Central Hudson Gas and
Electric Corp.
Consolidated Edison Company of New York Inc.
Lung Island Lighting ComPanY-
New England Electric
Systems.
New York State Gas and
Electric Assn.
Niagara Mohawk Power
Corporation.
tions have been given to all operators.
Additional recording meter installed. All recording equipment
at key stations provided with
emergency power independent
of system service.
Battery & emergency AC power
supplies insure continuity of
records without system service.
Two additional frequency meters
installed at control center to
provide additional records.
Oscillograpbs have been modified to provide longer postincident records.
Dual-range recording frequency
meters provided, with emergency
power supplies at dispatch center
and other major stations to
insure continuity of records.
TABLE
B-2.S!
Northeast U
Orange and
Utilities, I
Power Auth
State of N
Rochester C
fJm=Y
Recording devices provided with
auxiliary power supply to insure
continuity of record under emergency conditions.
Emergency generating equipment
at key station assures power
supply for recorders and telemetering under all conditions.
Dual speed meters provided at all
division control centers. Auxiliary
power supplies installed at district
operators centers and other key
locations to insure power for data
transmission.
gate wha
thermal I
on Novel
vestigate
System 01
dition of :
the Nove
an analyl
Force co
ernors re
position
too mud
consideri
opinion (
abnorma
TABLE B-2.-Communica~ion.r, Indnmwhtion and Data Tran.rmissimr4i’n$cant
Syskm Improuemcnt~ Since JVm. 9, 1965-Continued
System
Operator’s communications and aids
Northeast Utilities. . . . . .
Reserve alarm system provided at CONVEX control
center at Southington. Warnings provided for transmission line flows in excess of normal limits. Telephone
system revamped to provide direct-line communications with all outlying manned stations either individually or as a group. A “management” center with
separate unlisted lines provided to separate management and operations communications during emergency periods.
New emergency power supply installed at dispatch center and at other major stations. New dual-range,
multi-speed meter provided at dispatch center. Audio
and visual enunciator signals indicate change in range
at 59.7 cycles. Private leased telephone lines installed
between dispatch and other major operating stations.
Direct communications provided to neighboring utilities. Emergency alarm indicates tie line loads approaching limits at major interconnections.
Single-range meters provided at each station. Communicat+ improvements will provide assured service to
Syracuse control center to eliminate problems of the
type that developed on’ November 9 in connection
with initiating needed switching operations. A battery
powered communications power source has been installed at PASNY New York City Oflice. Emergency
radio power provided at all stations.
Emergency lighting installed in Andrew control center,
and new 60 kw power unit installed for additional
emergency power. Unlisted telephone numbers assigned to key personnel and key stations, direct line
telephone circuits between stations not dependent on
telephone company switchboards. Battery system provided for emergency telemetering. Dual-route microwave channels leased from telephone company for
some relay-control activities.
Orange and Rockland
Utilities, Inc.
Power Authority of the
State of New York.
Rochester Gas and Electric
Company.
gate what had occurred in the various operating
thermal plants at the time of the system disturbance
on November 9, 1965. The assignment was to investigate specifically the reaction of the ENY-NE
System operating thermal plants to the unusual condition of frequency and voltage which existed during
the November 9 system disturbance. On the basis of
an analysis of the information obtained, the Task
Force concluded that in general the turbine governors responded properly by going to the wide open
position with the drop in frequency, but there was
too much load for the available generating facilities
considering their possible rate of response. It is&e
opinion of the Station Operation Task Force that
abnormal system conditions resulting in a rapid fre-
Recordii equipment
Wide-range frequency meter provided with speedup arrangement
for emergencies. Butane “tertiary”
unit keeps recording charts moving
for few seconds between loss of
system service and full-speed operation of automatic auxiliaries.
New emergency power supplies pro-
vided at all major stations to provide continuous service to recording devices under any foreseeable
system conditions. New metering
equipment provides improved
records.
Rearrangements in station service
facilities will insure continuity of
records during emergency periods.
Delay devices being installed on
oscillographs to provide one or
two cycles of pre-fault information.
Fly-wheel-inertia provided with station power system to give continuous records during changes of
station power source. Recording
frequency meters installed on
split busses to provide record in
case of loss of service on part of
system. Meters are dual range.
Totalizing meters added to provide tie-line data. Additional oscillographs have been installed, and
time-stamp facilities installed.
quency decay call for an immediate, well-planned
fully coordinated and automatic or manual load
shedding procedure to quickly arrest the frequency
reduction. This should be accomplished prior to a
low frequency of 58.5 cycles which, according to the
major turbine manufacturers, is the critical
frequency for continuous full load operation of
turbines.
Recently, the Northeast Power Coordinating
Council adopted an automatic load shedding program. The specifications for this program are summarized in chapter 2, of this report. The load reduction policies which are currently in effect, and will
continue until the automatic system is installed, are
indicated in table I34.
161
TABLE B3.--Spinning Rmr~cs, Northeast Power +tms
-
Group or System
1966
S tern
r
hi”
7
S stem
apa6.
I12bztJ6
Capac- Capacity of
ity of
LEys’ Lp!Ke;’
M”w
MW
Coord.
Group for
Reserve
Requirement 4
Re uired
Avar9ability
Basis for
Reserve
Requirement
_BostonFdiinCo.....
Central Hudson Gas &
Elec. co.
Central Maine Power
co.
Central Vt. Public
krv. Corp.
Consolidated Edison
co.
Eastern utilities
Associates.
Green Mountain Power
Corp.
Holyoke Water Power
co.
Long Island Lighting
co.
New England Electric
systems.
New England Gas &
Elec. Assoc.
N.Y. State Elec. &
Gas Corp.
Niagara Mohawk Power Corp.
Northeast Utilities. . . .
Orange & Rockland
Utilities, Inc.
Power Authority-State
of N.Y.
Public Serv. Co. of
N.H.
Rochester Gas &
Electric Corp.
United Illuminating
co.
Yankee Atomic Electric
co.
c
rota1
(‘1
1
-E
System
In one
minute
-
Boston Edison
-s
Percent
MW
82
53
40
...
32
0
45
14
34
40
13
14
6
40
2
9
923
. . ..
0
180
23
40
7
6
--
1,442
393
1,742
340
359
147
469
293
ECCNE
NYPP
559
703
114
214
ECCNE
15..........
Max. Pool
u n i t + 2OfI.
6% Pool . . . .
199
98
13
31
ECCNE
6% Pool.. . . .
6, 154
7,477
1,028
1,828
NYPP
382
408
125
325
ECCNE
Max. Pool
U n i t + 2Of1.
6% Pool. . . . .
147
83
17
30
ECCN’E
6% Pool.. . . .
5
40
2
6
136
136
ECCNE
6% Pool. . . . .
4
40
2
2
187
. ..
0
187
106
40
40
40
72
-
(‘1
1,555
1, 606
188
467
NYPP
1,980
1,895
241
482
ECCNE
Largest Pool
Unit + 2Ot).
6% Pool.. . . .
330
251
33
131
ECCNE
6% Pool.. . . .
19
40
8
18
1,150
847
135
270
NYPP
45
25
11
10
3,987
3,067
218
828
NYPP
165
. . ..
0
45
2,934
293
3, 106
368
240
180
479
295
ECCNE
NYPP
131
37
40
...
50
0
50
10
636
3, 200
150
1,954
..........
Pool Peak +
300.
Pool Peak +
300.
6% ECCNE.
Largest Pool
Unit + 200 ‘.
20% of total.
400
50
200
200
476
471
114
190
ECCNE
6% Pool.. . . .
28
40
11
24
592
502
82
253
NYPP
90
. . ..
0
10
261
ECCNE
Pool Peak +
300.
6% Pool. . . . .
35
40
14
14
. . ..
....
605
(9
180
176
(9
....
......
0)
-
............
.
.
.....
Central Huds
Central Mair
Central Verr
Consolidated
Eastern Utll
Green Mom
Power.
Holyoke Wa
Power.
Long Island
Lighting.
-
1 In each case, total reserve requirement is to be provided in five minutes.
s CONVEX totals shown under Northeast Utilities.
s Included above.
4 Coordinating Groups are listed in Appendix C.
New Englar
tric Syster
New Englar
and Elect
N.Y. State.
and Gas.
1 LD--L
162
E
TABLE B-4.--Load
System
fethod
I
Reduction Procedures; Utilities Affected by the .Northcast Power Zntcnuption
Procedure
T
Percent reduction
60-59
--
cycles
59-58.5
cycles
Other
hvised
operaor9 in-
Remarks
StIllC-
tions
--
BostonEdison......
LD
Manual.. .
10
15
................
Central Hudson. . . . .
1 ;D
Manual. . .
10
15
Yes
Central Maine. . . .
1 >D
10
15
Central Vermont. . . .
Consolidated Edison .
1 >D
’i7R
1 ;D
Manual and
Automatic.
Manual.. .
Automatic
and
Manual.
1perator’s instruct
provides for load
reduction up to
108 Mw, or ovu
3070 of system
peak, in case of
emergency.
...............
10
5
5
15
3
12
...............
................
{es
[es
Eastern Utilities. . . .
Green Mountain
Power.
Holyoke Water
Power.
Long Island
Lighting.
1 ;D
1 ;D
Manual. . .
Manual. . .
10
10
15
15
...............
...............
[es
(es
LD
Manual. . .
10
15
LD
VR
Manual. . .
Manual. .
......
......
15
3
New England Electric Systems.
New England Gas
and Electric.
N.Y. State Electric
and Gas.
LD
Manual.. .
LD
LD
VR
tea
Under-frequency relays installed to activate automatic voltage reduction
mechanism. System involves 101 relays at 15
stations. Reduction is at
rate of 1 yo per 1 o/o reduction in voltage.
YCS
YCS
YCl
15
Instructions to op
erators provide
for combined
voltage reductio
& load dropping, after freq.
drops to 58.5 or
lower, up to
600 mw (35%).
...............
Manual. . .
15
. . . . . . . ...*.....
YC.9
Manual.. .
Manual. . .
15
...............
YCS
1 LD-Load dropping; VR-Voltage reduction.
Load shedding controlled
from buttons in diipatch
office, with one button
for first lo?&, a second
button for next 15%, a
thiid button to initiate
tie-line opening if frequency is below 58.5
cycles and falling. Two
additional buttons provide relief above 25% if
necessary. Protection
provided to insure
against accidental load
shedding.
New supervisory control
equipment provided to
permit load dropping
from dispatch center.
If frequency continues to
drop below 58.5 cycles,
the interconnection with
Con Ed will be opened
and additional system
load will be dropped
until frequency has
been stabilixed.
YCS
Automatic load dropping
under study.
163
TABLE H.--Load
Reduction Procedures; Utilities Affected by the Northeast Power Znterrupion-Continued
-
ISystem
Method
Procedure
Percent reduction
60-59
cycles
59-58.5
cycles
Other
Revised
operators instructions
Niagara Mohawk.
LD
Automatic
and
Manual.
10
15
................
YeS
Northeast Utilities..
LD
Manual....
10
15
................
YtS
Orange and Rockland.
LD
Manual and
Automatic.
10
15
Load dropping
proceeds to 100
mw total, which
is at least 30%
of load.
YeS
PASNY. . . . . . . . . .
LD
Manual....
10
15
................
YeS
Public Service of
New Hampshire.
Rochester Gas and
Electric.
United Illuminating
LD
Manual....
10
15
................
YC3
LD
Manual....
10
15
................
YCS
LD
Manual....
10
15
................
Yt!S
1 LD-Load dropping; VR-Voltage reduction.
Remarks
Automatic equipment
drops up to 850 megawatts of industrial load
at various frequencies
down to 58.5 cycles.
Automatic load dropping
under study.
Operator’s instructions indicate switches to be
opened for each level of
load relief. At 59.5
cycles Mongaup hydra
unit isolated from
system.
Most PASNY power sold
to other utilities, so load
shedding, per se, not
significant factor in
PASNY operations.
Procedures for load shedding under study.
Mechani
Electric
of
and opera
coordinati
“formal p
ma1 powe
more elecl
coordinatt
economy ;
bined loac
rangemen
capacity a
procedure
requireme
opinion as
can be inc
so defined
groups of
In addi
a number
tern plan1
vary wide
tiveness. 5
for the cc
statistical
and plana
cilities. 0
ing about
planned 5
present ti
formed w
system rel
Chapte
the print
and short
groups nc
ing areas
and the 1
bers of ea
shown in
variety
APPENDIX C
MAJOR COORDINATING ORGANIZATIONS
Mechanisms for Coordination
Members of Major Formal Power Pools
Electric power systems have developed a wide
variety of mechanisms for coordination of planning
and operation. The most fully developed form of
coordination at the present time is the so-called
“formal power pool”. In the present context, formal power pool should be taken to mean ,two or
more electric systems which are interconnected and
coordinated for the purpose of achieving greater
economy and reliability in the supply of their combined loads in accordance with a contractual arrangement which provides for the exchange of
capacity and energy among them and establishes a
procedure for the sharing of their generating reserve
requirements. There may be some difference of
opinion as to whether one or a few individual groups
can be included within the concept of power pools
so defined, but it is clear that there are at least 18
groups of systems that can reasonably be included.
In addition to *the formal power pools, there are
a number of organizations that engage in inter-system planning on an area or regional basis. They
vary widely in size and functions as well as effectiveness. Some appear to be little more than centers
for the collection, organization and distribution of
statistical information concerning load projections
and plans for new generation and transmission facilities. Others have been highly effective in bringing about the construction of bulk power facilities
planned and engineered on a regional basis. At the
present time, only two regional groups have been
formed whose principal function is improvement in
system reliability.
Chapter 4 of the main report discusses some of
the principal characteristics, objectives, functions
and shortcomings of the power pools and planning
groups now in existence. It also includes maps showing areas covered by 18 major formal power pools
and the 11 major power planning groups. The members of each of these pools and planning groups are
shown in the following lists.
Connecticut Valley Electric Exchange (CONVEX)
Connecticut Light & Power Company
Hartford Electric Light Company
United Illuminating Company
Western Massachusetts Electric Co.
New York State Power Pool
Central Hudson Gas & Elecrtic Corporation
Orange and Rockland Utilities, Inc.
Consolidated Edison Company of N. Y.
Long Island Lighting Company
Niagara Mohawk Power Corp.
New York State Electric and Gas Corp.
Rochester Gas and Electric Corp.
Pennsylvania-New Jersey-Maryland Interconnection (P]M)
Public Service Electric and Gas Company
Philadelphia Electric Company
Pennsylvania Power and Light Company
Baltimore Gas & Electric Company
Potomac Electric Power Company
General Public Utilities Corporation
Metropolitan Edison Company
Pennsylvania Electric Company
Jersey Central Power and Light Company
New Jersey Power and Light Company
Associate Members
Delmarva Power & Light Company
Atlantic City Electric Company
Luzerne Electric Division, United Gas Improvement Company
Carolinas-Virginias Power Pool (CARVA)
Virginia Electric & Power Company
Carolina Power & Light Company
Duke Power Company
South Carolina Electric & Gas Company
American Electric Power System
Appalachian Power Company
Indiana & Michigan Electric Company
Kentucky Power Company
American Electric Power System-Continued
Ohio Power Comapny
(Kingsport Power Co. and Wheeling Electric Co., which are part of AEP, have no
generation.)
Allegheny Power System
Monongahela Power Company
Potomac Edison Company
West Penn Power Company
Southern Company System
Alabama Power Company
Georgia Power Company
Gulf Power Company
Mississippi Power Company
(Southern Electric Generating Co., which is
part of the Southern Company System,
was formed by Alabama Power Co. and
Georgia Power Co. to construct a generating plant owned jointly by the two companies. )
Middle South Utilities Power Pool
Arkansas Power & Light Company
Louisiana Power & Light Company
Mississippi Power & Light Company
(New Orleans Public Service, Inc., is a subsidiary of this holding company but is not
a pool member; it has an interchange
agreement with Louisiana Power & Light
Company.)
Illinois-Missouri Pool
Central Illinois Public Service Company
Illinois Power Company
Union Electric Company
(Electric Energy, Inc. is owned by these
three companies. Missouri Edison Co. and
Missouri Power & Light Co. are wholly
owned subsidiaries of Union Electric
Company.)
Missouri-Kansas Pool
Empire District Electric Company
Kansas City Power & Light Company
Kansas Gas & Electric Company
Kansas Power and Light Company
Missouri Public Service Company
Upper Mississippi Valley Power Pool
Cooperatives
Cooperative Power Association
Dairyland Power Cooperative
Minnkota Power Cooperative
Northern Minnesota Power Association
Rural Cooperative Power Association
United Power Association
Investor-owned
Companies
Interstate Power Company
166
Lake Superior District Power Company
q
Minnesota Power & Light Company
Montana-Dakota Utilities Co.
Northern States Power Company (Minn.)
Northern States Power Company (Wise.)
Northwestern Public Service Company
Otter Tail Power Company
Iowa Power Pool
Iowa Electric Light and Power Company
Iowa-Illinois Gas and Electric Company
Iowa Power and Light Company
Iowa Public Service Company
Iowa Southern Utilities Company
Corn Belt Power Cooperative
California Power Pool
Southern California Edison Company
Pacific Gas and Electric Company
San Diego Gas & Electric Company
Indiana Power Pool
Indianapolis Power & Light Company
Public Service Co. of Indiana
Wisconsin Power Pool
Wisconsin Public Service Company
Wisconsin Power and Light Company
Michigan Pool
Consumers Power Company
Detroit Edison Company
Northwest Intercompany Pool
Puget Sound Power & Light Company
Pacific Power & Light Company
Portland General Electric Company
Washington Water Power Company
Northwest Coordination Group
Bonneville Power Administration
City of Eugene, Oregon
City of Seattle, Washington
City of Tacoma, Washington
Colockum Transmission Company
Montana Power Company
Pacific Power & Light Company
Portland General Electric Company
P.U. Dist. No. 1 of Chelan County, Washington
P.U. Dist. No. 1 of Cowlitz County, Washington
P.U. Dist. No. 1 of Douglas County, Washington
P.U. Dist. No. 1 of Pend Oreille County, Washington
P.U. Dist. No. 2 of Grant County, Washington
Puget Sound Power & Light Company
United States Corps of Engineers
Washington Water Power Company
Aembers
Groups
Associated 11
Idaho P
Montan
Pacific 1
Utah PC
Washin!
C e n t r a l A1
( CAPCO:
Appalac
Clevelai
Duques
Indiana
Mononl
Ohio E
Ohio PI
Pennsyl
Potoma
Toledo
West P
East Centra
ment
Appala
Cincini
Cleveli
ColUml
Pam
Daytor
Duque
Indian
Indian
Indian
Kentut
Kentu’
Louisv
Mono]
North1
Ohio 1
Ohio 1
Ohio ’
Penns
Poton
Public
South’
Toled
West
Electric Cc
Bang<
Bosto:
Centr
267-7
Aembers of Major Power Planning
Groups
Associated Mountain Power Systems
Idaho Power Company
Montana Power Company
Pacific Power & Light Company
Utah Power & Light Company
Washington Water Power Company
Central Area P o w e r Coordination Group
(CAPCO)
Appalachian Power Company
Cleveland Electric Illuminating Company
Duquesne Light Company
Indiana & Michigan Electric Company
Monongahela Power Company
Ohio Edison Company
Ohio Power Company
Pennsylvania Power Company
Potomac Edison Company
Toledo Edison Company
West Penn Power Company
East Central Area Reliability Coordination Agreement
Appalachian Power Company
Cincinnati Gas & Electric Company
Cleveland Electric Illuminating Company
Columbus and Southern Ohio Electric ComPanY
Dayton Power and Light Company
Duquesne Light Company
Indiana & Michigan Electric Company
Indiana-Kentucky Electric Corporation
Indianapolis Power & Light Company
Kentucky Power Company
Kentucky Utilities Company
Louisville Gas and Electric Company
Monongahela Power Company
Northern Indiana Public Service Company
Ohio Edison Company
Ohio Power Company
Ohio Valley Electric Corporation
Pennsylvania Power Company
Potomac Edison Company
Public Service Company of Indiana, Inc.
Southern Indiana Gas and Electric Company
Toledo Edison Company
West Penn Power Company
Electric Coordination Council
of
New England
Bangor Hydro-Electric Company
Boston Edison Company
Central Maine Power Company
267-7810-67-12
Central Vermont Public Service Corporation
Connecticut Light and Power Company
Eastern Utilities Associates
Fitchburg Gas and Electric Light Company
Green Mountain Power Corporation
Greenville Electric Lighting Company
Hartford Electric Light Company
Holyoke Water Power Company
Maine Public Service Company
New England Electric System
New England Gas and Electric Association
Newport Electric Corporation
Public Service Company of New Hampshire
Rangeley Power Company
United Illuminating Company
Western Massachusetts Electric Company
Mid-America Interpool Network (MAIN)
American Electric Power System
Appalachian Power Company
Indiana and Michigan Electric Company
Ohio Power Company
Kentucky Power Company
Kingsport Power Company
Wheeling Electric Company
Commonwealth Edison System
Illinois-Missouri Pool
Central Illinois Public Service Company
Illinois Power Company
Union Electric Company
Indiana Power Pool
Indianapolis Power and Light Company
Public Service Company of Indiana
Wisconsin Planning Group
Madison Gas and Electric Company
Wisconsin Electric Power Company
Wisconsin Michigan Power Company
Wisconsin Power and Light Company
Wisconsin Public Service Corporation
Mid-Continent Area Power Planners (MAPP)
Canadian Crown Corporation
Manitoba Hydro-Electric Board
Investor-Owned Electric Utility Companies
Black Hills Power and Light Company
Interstate Power Company
Iowa Electric Light and Power Company
Iowa-Illinois Gas and Electric Company
Iowa Power and Light Company
Iowa Public Service Company
Iowa Southern Utilities Company
Lake Superior District Power company
Minnesota Power & Light Company
Montana-Dakota Utilities Company
Mid-Continent Area Power Planners--Con.
Investor-Owned Electric Utility Companies-
Continued
Northern States Power Company
Northwestern Public Service Company
Otter Tail Power Company
Union Electric Company
Municipal Electric Utilities
Ames, Iowa
Austin, Minnesota
Cedar Falls, Iowa
Delano, Minnesota
Glencoe, Minnesota
Hutchinson, Minnesota
Lake Crystal, Minnesota
Madelia, Minnesota
Marshall, Minnesota
Mazeppa, Minnesota
Melrose, Minnesota
Moor-head, Minnesota
New Ulm, Minnesota
Owatonna, Minnesota
Redwood Falls, Minnesota
Sleepy Eye, Minnesota
Watertown, South Dakota
Public Power District
Omaha Public Power District
Rural Electric Cooperatives
Cooperative Power Association
Dairyland Power Cooperative
Eastern Iowa Light and Power Cooperative
Minnkota Power Cooperative
Northern Minnesota Power Association
Rural Cooperative Power Association
Missouri Basin Systems Group
Bureau of Reclamation
Loup River Public Power District, Nebraska
Platte Valley Public Power and Irrigation District, Nebraska
State of Nebraska, Department of Public Institutions
University of Nebraska
Municipal Electric Systems
Aberdeen Municipal Utilities, South Dakota
Adrian, Minnesota
Akron Municipal Light & Water Works,
Iowa
Alta Municipal Power Plant, Iowa
Anita Municipal Utilities, Iowa
Arlington Municipal Light & Power, South
Dakota
Atlantic Municipal Utilities, Iowa
168
Badger Utility, South Dakota
Beatrice Board of Public Works, Nebraska
Beresford Utility, South Dakota
Big Stone City Utility, South Dakota
Breda, Iowa
Brewster Municipal Light & Power, Minnesota
Burke Utility, South Dakota
Callaway, Nebraska
Cavalier City Light & Water Plants, North
Dakota
Coon Rapids Municipal Utilities, Iowa
Den&on Municipal Utilities, Iowa
Elk Point Light & Water, South Dakota
Estelline Utilities, South Dakota
Fairfax Municipal Power Plant, Minnesota
Faith Utility, South Dakota
Fort Pierre Utility, South Dakota
Gowrie Municipal Utilities, Iowa
Graettinger, Iowa
Grafton Utilities, North Dakota
Grove City Utility, Minnesota
Harlan Municipal Utilities, Iowa
Hawarden Municipal Utilities, Iowa
Henning Electric, Minnesota
Hillsboro Utilities, North Dakota
Hope City Light and Power, North Dakota
Jackson Municipal Light Plant, Minnesota
James Valley Electric Power Cooperative,
North Dakota
Kimballton Municipal Light & Power, Iowa
Lake Park Municipal Utilities, Iowa
Lakefield Public Utilities, Minnesota
Lakeview, Iowa
Lakota Utilities, North Dakota
Lang-ford Municipal Electric, South Dakota
Laurens Municipal Light & Power Plant, Iowa
Lenox Municipal Light and Power, Iowa
Litchfield Public Utilities Commission, Minnesota
Maddox Utility, North Dakota
Madison Electric Utility, South Dakota
Manilla Municipal Service Department, Iowa
Manning Municipal Light Plant, Iowa
Mapleton Municipal Electric Plant, Iowa
Melrose Utility, Minnesota
Milford Municipal Light Plant, Iowa
Miller Utility, South Dakota
Mountain Lake, Minnesota
Nebraska City, Nebraska
Onawa Municipal Utilities, Iowa
Orange City Municipal Utilities, Iowa
Parker Municipal Light Plant, South Dakota
Paullina L
Pierre Mu
Primghar 1
Remsen h4
Rock Rap
St. James 1
sanborn h
Sharon Vi1
Shelby Mt
Sibley Util
Sioux Cen
Spencer h,
Stanton, I
Stephen E
Tyler MUI
Tyndall L
Valley Cit
’ Vermillior
Dakota
Volga Pou
Wadena
nesota
Wall Lake
Water-tow
south I
Wessingtc
Power,
Westbroo
nesota
Woodbinc
Rural Elect!
Baker E
Dakota
Basin Ele
Dakota
Big Flat
Big Herr
Monta
Central 1
Gentral
Dakot:
Cherry-l
Dakou
Corn Be
Dakota
Dakot;
East Riv
Dakot
Grand
Dakot
Paullina Utility, Iowa
Pierre Municipal, South Dakota
Primghar Municipal, Iowa
Remsen Municipal Utilities, Iowa
Rock Rapids Municipal .Utilities, Iowa
St. James Electric Utility, Minnesota
Sanborn Municipal Light Plant, Iowa
Sharon Village Light and Power, North Dakota
Shelby Municipal Utility, Iowa
Sibley Utility, Iowa
Sioux Center Municipal Utility, Iowa
Spencer Municipal Utilities, Iowa
Stanton, Iowa
Stephen Electric Department, Minnesota
Tyler Municipal Utilities, Minnesota
Tyndall Utility, Minnesota
Valley City Municipal Utilities, North Dakota
‘Vermillion City Light and Power, South
Dakota
Volga Power and Light, South Dakota
Wadena Light & Water Department, Minnesota
Wall Lake, Iowa
Watertown Municipal Utilities Department,
South Dakota
Wessington S p r i n g s M u n i c i p a l L i g h t &
Power, South Dakota
Westbrook Municipal Light & Power, Minnesota
Woodbine Municipal Light & Power, Iowa
Rural Electric Cooperatives
Baker Electric Cooperative, Inc., North
Dakota
Basin Electric Power Cooperative, Inc., North
Dakota
Big Flat Electric Cooperative, Inc., Montana
Big Horn Country Electric Cooperative, Inc.,
Montana
Central Montana Electric G&T, Montana
43entral Power Electric Cooperative, North
Dakota
Cherry-Todd Electric Cooperative, South
Dakota
Corn Belt Power Cooperative, Iowa
Dakota Electric Cooperative, Inc., North
Dakota
East River Electric Power Cooperative, South
Dakota
Grand Electric Cooperative2 Inc., South
Dakota
Hill County Electric Cooperative, Inc., Montana
KEM Electric Cooperative, Inc., North
Dakota
L&O Power Cooperative, Iowa
Lyon-Lincoln Electric Cooperative, Minnesota
Marias River Electric Cooperative, Inc., Montana
McCone Electric Cooperative, Inc., Montana
Minnesota Valley Light and Power Association, Minnesota
Moreau-Grand Electric Cooperative, South
Dakota
Mor-Gran-Sou Electric Cooperative, Inc.,
North Dakota
Nebraska Electric G&T Cooperative, Inc., Nebraska
Nodak Rural Electric Cooperative, Inc., North
Dakota
Northwest Iowa Power Cooperative, Iowa
Park Electric Cooperative, Inc., Montana
Renville-Sibley Cooperative Power Association,
Minnesota
Rosebud Electric Cooperative, Inc., South
Dakota
Rushmore Electric Cooperative, Inc., South
Dakota
Sheyenne Valley Electric Cooperative, North
Dakota
T&State G&T Association, Colorado
Upper Missouri G&T, Montana
Verendrye Electric Cooperative, Inc., North
Dakota
Yellowstone Valley Electric Cooperative, Inc.,
Montana
Southwest Power Pool
Arkansas-Missouri Power Company
Arkansas Power & Light Company
Central Louisiana Electric Company, Inc.
Empire District Electric Company
Gulf States Utilities Company
Kansas Gas and Electric Company
Louisiana Power & Light Company
Mississippi Power & Light Company
Missouri Public Service Company
Missouri Utilities Company
New Orleans Public Service, Inc.
Oklahoma Gas and Electric Company
Public Service Company of Oklahoma
Southwestern Electric Power Company
Western Power and Gas Company, Inc.
169
Western Energy Supply B Transmission ASSOciates ( W E S T )
Arizona ElectricPower Cooperative
Arizona Public Service Company
City of Burbank, Public Service Department
City of Colorado Springs, Department of Public
Utilities
Colorado-Ute Electric Association
El Paso Electric Company
City of Glendale
Imperial Irrigation District
City of Los Angeles, Department of Water and
Power
Nevada Power Company
Pacific Power & Light Company (Wyoming
Division)
Pasadena Municipal Light & Power Department
Plains Electric G&T Cooperative
?ublic Service Company of Colorado
Public Service Company of New Mexico
Salt River Project
San Diego Gas & Electric Company
Sierra Pacific Power Company
Southern California Edison Company
Tucson Gas & Electric Company
Utah Power & Light Company
Northeast Power Coordinating Council
Boston Edison Company
Central Hudson Gas & Electric Corporation
Central Maine Power Company
Central Vermont Public Service Corporation
Connecticut Light and Power Company
Hartford Electric Light Company
Western Massachusetts Electric Company
Consolidated Edison Company of New York,
Inc.
Blackstone Valley Electric Company
Brockton Edison Company
Fall River Electric Light Company
Montaup Electric Company
Green Mountain Power Corporation
Holyoke Water Power Company
Hydro-Electric Power Commission of Ontario
Long Island Lighting Company
Cambridge Electric Light Company
New Bedford Gas and Edison Light Company
Cape and Vineyard Electric Company
Plymouth County Electric Company
New England Power Company
Massachusetts Electric Company
This Apl
tad impact
activities ar
marizes the
state, munil
the event a
ments to m
Because of
wide diitril
agencies of
sion considc
informatior,
of the infor
mission’s in
of agencies
General
Transpol
large metro
early eveni
New York
electric POT
sands of pe
tions, in tu
electric mc
have offere
because tra
However,
used effect
town busir
more than
portation v
station pui
stalled car
commercia
for three
continued
electric ger
Railroac
in the Neon
170
_“,
.
:.
APPENDIX
D
IMPACT OF POWER FAILURES
This Appendix enumerates some of the important impacts of the Northeast power failure on the
activities and welfare of the area affected and summarizes the investigations and activities of Federal,
state, municipal and other authorities in reviewing
the event and in examining preparedness requirements to minimize effects of major power failures.
Because of the importance of this subject and the
wide distribution of responsibilities among many
agencies of all levels of government, the Commission considered that it would be helpful to compile
information on actions taken and planned. A digest
of the information received in response to the Commission’s inquiry on this subject to a large number
of agencies is included in this Appendix.
General Impacts
Transportation
Transportation facilities and equipment in the
large metropolitan areas were meeting their normal,
early evening peaks at the time of the outage. In
New York City, the sudden interruption of the
electric power supply stranded hundreds of thousands of people in elevators, on trains between stations, in tunnels under rivers and on bridges. Nonelectric motor bus service, which normally could
have offered some relief was rendered less effective
because trafhc control systems became inoperative.
However, in New York City the bus system was
used effectively to evacuate people from the downtown business districts, where on an average day
more than a million people are employed. Transportation was further hampered because most filling
station pumps could not be operated. Occasional
stalled cars added to traffic congestion. Although
commercial power service in Boston was interrupted
for three to eight hours, Boston’s subway system
continued in operation with power from its own
electric generating facilities.
Railroad passenger service was extremely limited
in the New York City metropolitan area until 5:00
a.m., November 10 and was erratic throughout the
Northeast because of the wide dependence upon
commercial power sources for the operation of signaling and switching devices.
Air transportation for the most Fart fared somewhat better than the railroads or subways. Aided
by clear weather and some auxiliary and improvised
emergency power facilities to energize essential traffic control systems, most airports were able to continue functioning on a restricted basis. LaGuardia,
for example, handled 246 flights during the emergency period. However, many flights were cancelled, delayed or diverted to airports outside the affected area. New York’s LaGuardia and John F.
Kennedy Airports were without adequate power
for about 12 hours. Fortunately, power service to
the Newark Airport was not interrupted and flight
accommodations at this field were extended to receive about 70 diverted flights.
Interstate and intrastate motor bus and line haul
freight carriers were not affected in their operations
except for delays caused by increased traffic congestion in some areas.
Marine terminals, canal and ocean shipping operations were also minimally affected since ships
generate their own power and navigational aids and
canal locks generally have auxiliary or self-contained power units.
Public Service
The massive power interruption had a significant
effect on such essential functions as water and sewage service, particularly for high-rise buildings.
Many persons were confined in elevators for varying periods of time.
Hospital procedures, medical equipment, and
drugs and blood supplies depend heavily upon electric energy for their use and maintenance. Fortunately, no grave effects in human care institutions
were reported as directly attributable to power failure. This was due mainly to the alertness and capability of hospital staffs and the cooperation of local
171
government services and some public utilities. At
the time of the power outage only five of New York
City’s 21 city-operated hospitals had their own generators, but local government services and public
utilities made available mobile generating units to
a number of hospitals that lacked auxiliary power.
In Massachusetts, of 142 hospitals responding to
an inquiry by the Massachusetts Hospital Association on auxiliary power availability during the
power outage, six hospitals reported no loss of
power, 11 sustained power losses of less than onehour duration, 23 experienced power losses for
periods of one to two hours ; the remaining 102 hospitals were without power for periods ranging from
two to over eight hours. Only four of the respondents
had no emergency generators. One hundred and
thirty hospitals reported having automatic switching devices, but about 10 percent reported some
switchover problems. Only four were unable to
start their generators. The Boston Regional Office
of the Department of Health, Education, and Welfare reported that while some of the hospitals in
Massachusetts are improving their emergency power
capabilities, there appear to be no legislative or
building code changes pending for the same purpose.
The threat to public safety from crime was appreciably minimized by the availability of self-contained power units in most law enforcement facilities. Fortunately, the number of fires during the
blackout was low.
Communications
Keeping a large electric power-deprived population continuously informed about the power failure
was psychologically important. Initially, radio
broadcasts assured all listeners that the cause was
primarily of mechanical origin and not due to sabotage or enemy action. The broadcasting industry was
also helpful in preparing and delivering special announcements on traffic and travel conditions, suggestions on the prevention of food spoilage and statements concerning services affected by the blackout.
Within minutes after the power failure, 61 standard
broadcast stations, 18 FM stations, and 12 TV stations resumed operation with emergency generators,
and within a two hour period, 12 1 standard broadcast stations, 47 FM stations and 19 TV stations located in the affected area had been restored to service. The value of battery-powered radio receiving
sets was amply demonstrated.
172
The affected area involved 16 million telephones
and 1,380 communications equipment centers. The
various telephone companies, supported by their
own emergency power, continued to operate when
commercial power failed. Although loads were abnormally heavy, priority calls and mdst of the regular
calls were completed without service difficulty.
There were delays in some instances, due to circuit
overloading. Little difficulty was experienced in
maintaining government communication services.
The major problems encountered concerned equipment which depended upon local power sources for
operation, such as teletypewriters and PBX switchboards.
Telegraphic service was delayed up to 14 hours.
Although some auxiliary power equipment was
available outside the New York City area, service
was not assured to customers due to the lack of commercial power at most telegraph branch offices and
to customers using private wire service.
The overall impact on critical national security
communications was negligible, due mainly to the
availability of emergency standby power and the
alternative routing capability of the defense services. Similarly, the overall effect of communication
losses on the critical functions of Federal government agencies in the affected area was minor due to
the availability of priority service and the fact that
the event occurred during a period which normally
has a very low communications traffic demand.
Agency Actions
In order to assess the impact of the November 9th
power failure on significant aspects of human and
institutional activities throughout the affected area
and the country at large, the Commission sent letters to approximately 30 Federal, state, and local
agencies requesting the following information : ( 1)
a summary of their investigations and findings relating to a given list of essential services, (2) a list
of specific actions taken, or in process, directed towards preventing or alleviating the impact on these
services in the future should a power failure occur,
and (3) their suggestions for additional services considered sufficiently important to be supported by
emergency electric power facilities. The reported
activities of several of the agencies having important
responsibilities for essential services are summarized
in the sections which follow. Table D-l shows the
emergency services that have been suggested or required at selected essential service facilities.
Item
Operating Rot
X-Ray.....
Emergency Re
Area. . . . . . .
Recovery ROOI
Intensive Care
Elevator Se&
Corridor & Ex
Stairwell Lighl
Alarm & Call !
Heating/Cooli
tilation.. . . .
Refrigeration :
Minimal Food
Pumps, Fuel,
Lubrication
Air Compressc
Exterior Lighl
Tower......
Lights, Runwi
Phones, Switc
boards, Rat
typewriterv
1 Include!
s Includes
s Includes
Fee
As a resu
of dependir
port of tllf
was modifi
engine get-r
The agent;
nation as 0
with adeqc
full operat
least one m
failure. Th
apart were
tion to pra
of an area1
of the airy
engine gen
lations are
all of the
November
TABLE
Item
Operating Rooms
X-Ray. . . . . . . . . . .
Emergency Receiving
Area..............
ReeoveryRooms.....
Intensive Care Areas. ,
Elevator Service.. . . .
Corridor & Exit Light!
Stairwell Lights. . . .
Alarm & Call System 1
Heating/Cooling/Ventilation.. . . . . . . . . . .
Refrigeration s. . . . . .
Minimal Food Service
pumps, Fuel, Vacuum
Lubrication &Motor
A i r Compressor.. .
Exterior Lighting.. . .
Tower. . . . . . . . .
Lights, Runway, Road
Phones, Switchboards, Radio, Tele.
typewriters . . . . . . .
Haspitals
D-l.-Sclectcd Essential Services Requiring Emergmcy Ehctric Power
Schools
Hotels
Apartments
Office
Bldgs.
Mwable
Bridges
......
......
......
......
......
......
......
......
.......
......
......
1Fog
X
X
X
X
X
X””
X
X
X””
X
X
X
......
......
......
......
......
X
X
X
X
X
X
X
......
......
X
......
......
......
......
......
X
X
X
. . . .
.
......
......
......
......
......
......
.....
. . . .
. . . . .
.
......
......
......
......
......
X
X””
......
......
X
X
X
X
X
xa
Airports
Railroad h
Rapid
Transit
Stations
and
Tunnels
Industrial
Produc:ion and
R&D
ties
Civil
Defenst
Operat
hi3
Centen
Law
En‘orce-
1 Includes fire protection.
s Includes heat removal from hydrogen and other cooling medii.
s Includes blood bank refrigeration.
Federal Aviation Administration
As a result of the power failure, the agency policy
of depending upon two prime power sources for support of the National Air Space System’s facilities
was modified to provide the addition of standby
engine generators for all critical operational needs.
The agency has identified 50 key airports across the
nation as continuous power airports, to be equipped
with adequate auxiliary power generators to permit
full operational capability of agency facilities on at
least one runway in the event of a commercial power
failure. These 50 airports, no more than 200 miles
apart were selected on the basis of activity and location to provide for recovery of aircraft in the event
of an areawide power outage. As of April 1967, two
of the airports had been equipped with the necessary
engine generators. Many of the remaining 48 installations are now approaching completion and almost
all of the installations will be fully completed by
November 1967. A number .of engine generators
have been loaned to airport sponsors to provide
backup power for runway lighting. Federal funds
are also available to airport sponsors under the Federal Aid to Airports Program, to help finance the
cost of permanent emergency power facilities for
runway and taxiway lighting. Battery-powered radio
transceivers are being procured for use as emergency
equipment at major air traffic control towers other
than at the 50 continuous power airports, and are
scheduled for complete installation by mid-March
1968. Additionally, the FY-1968 operations program is scheduled to provide the emergency power
equipment at Air Route Traffic Control Centers
with out-of-tolerance frequency sensing devices to
avoid shutdown of these essential facilities due to
variations in the frequency of commercial power.
Department of the Interior
All agencies of the Department concerned with
electric power generation, transmission or marketing
were asked to review their power systems for deficiencies following the Northeast outage. Responses
indicated that where such deficiencies were found,
corrective actions have been taken or are in progress.
These actions include improvements in communications and telemetering, station service power supply,
and circuit design.
Interior’s Office of Oil and Gas, concerned with
electric power requirements for oil and gas gathering, processing, production and transportation, requested the National Petroleum Council to
undertake a study of the adverse effects of massive
power failures on the oil and gas industry. The
Council reported that: ( 1) There is a very high
dependency upon purchased electric power in the
crude oil and products pipeline transportation and
refining phases of the industry. It also reported that
in the event of a massive power outage, damage to
equipment would be light, and would generally
center at those refineries unable to shut down in an
orderly fashion due to insufficient auxiliary steam
equipment. (2) The November 9 outage had no
major impact on the refinery industry. Only three
refineries in the Northeast area were directly affected; one was forced to shut down, the other two
continued operations by switching to auxiliary steam
equipment. The Council found that, although refineries constructed in the last 10 years are essentially
all-electric and would shut down in the event of a
power failure, they generally have sufficient auxiliary steam to permit a normal shutdown without
damage. The Council recommended that companies
planning to construct new facilities or expand
existing facilities consult with experts in the electric
power industry on such matters as auxiliary generating and pumping facilities. (3) Little, if any,
damage would be incurred by pipeline pumping or
compressor equipment in a massive power outage.
Practically all gas compressors and pumps are driven
by engines utilizing natural gas as a fuel. Standby
generators would be utilized, as is customary in
emergencies to control pipeline flows at reduced
rates.
Federal Communications Commission
The FCC’s critical direction finding and monitoring operations concerned with the practical aspects
of locating unauthorized stations, or sources of interference to broadcast and radio reception, measuring signal quality, and providing other similar
aids, are maintained through an interconnected
l&station communications network equipped with
174
auxiliary generators. Washington headquarters of
FCC is the exception; no emergency auxiliary
power generators are available at the Commission’s
.headquarters offices. In the event of a commercial
power failure in Washington, D.C., network control operations would be shifted automatically to
an alternative control center. Through the efforts
of the national and state Industry Advisory Committees, the broadcasting industry, common carrier
services and the safety and special radio services
have developed emergency plans and procedures
directed toward keeping telecommunications media
open and available to the public. Following the
Northeast power failure, system improvements have
been made in all sections of the telecommunications
industry, particularly where the absence of auxiliary
power facilities resulted in communications failures.
All major companies 1 have reviewed their systems’
weaknesses, as indicated by service failures during
the outage, and to the extent feasible have corrected or are in the process of correcting themessentially increasing the availability and reliability
of emergency power generating equipment and providing additional circuit capability. A problem not
completely resolved concerns the regular installation of power packs or other self-contained power
supply units on the customer’s premises, to activate
terminal equipment such as teletypewriters, facsimile transmission facilities, switchboards and telephone signal lights. The various reports furnished
to FCC indicate that the communications industry
has put forth strong efforts to meet emergency
service needs.
Department of Defense
The Northeast power failure had a relatively
minor impact on the Defense Communications
System. Critical defense functions were not impaired. An evaluation of all critical military voice
and record circuits has been undertaken to ferret
out weaknesses and to establish increased reliability.
Where emergency power installations were available and failed to perform as planned, corrective
measures have been taken to preclude a recurrence
of the difficulty. Where emergency power was absent, it has since been installed or is planned for
installation. Nationwide action has been initiated
on the defense warning system voice network to
1 Including The Western Union Telegraph CO., Western
Union International, RCA Communications, Inc., and
ITT World Communications, Inc.
assure that
central pow
ply. A joir
Military Dc
ing Groupmanship, i
worldwide 1
deficiencies.
availability
tions, incll
routings, al
variable vc
power syste
Gt
A progra
isting gove
emergency
cars, trand
centers, sti
gram is sch
of calendar
made for e
service ant
Federal bu
deemed ne
have been
power sup1
power soux
trict offices
speed telep
continued
bility. Batt
teletype tr
hours are
subscriber5
impact SUI
operations
Northeast
these opec
Departme
The De:
ban Mass
expenditur
elude pov
radio corn
and alarm
provide fu
ties under
lit Facilit
programs.
assure that all warning telephones have a reliable
central power source or a local battery power supply. A joint Defense Communications AgencyMilitary Departments Power Improvement Working Group-formed under permanent DCA chairmanship, is engaged in the resolution of any
worldwide Defense Communications Systems power
deficiencies. Re-examination of all factors affecting
availability and reliability of critical communications, including emergency power, alternative
routings, and the maintenance of operations with
variable voltage and frequency due to unstable
power system conditions will be undertaken.
General Services Administration
A program has been initiated to provide all existing government-owned buildings with needed
1 emergency power sources for lighting in elevator
cars, transformers and switchgear rooms, control
centers, stairwells and other critical areas. This program is scheduled to be completed prior to the end
of calendar year 1967. Provisions also are being
made for emergency power generation for elevator
service and other essential requirements in those
I
Federal buildings where ,this emergency service is
deemed necessary. All GSA-operated switchboards
have been equipped with an emergency battery
power supply. Similarly, the addition of emergency
power sources at message dispatch centers and district offices of the Advanced Record System (high
speed teletypewriter and data transmission) insures
continued operation of telegraphic switching capability. Battery power packs capable of operating a
teletype transmitter or receiver for at least eight
hours are made available at additional cost to
subscribers who need such service. A power outage
impact survey of GSA supply and material depot
operations concluded that power outages of the
Northeast proPortions would not seriously impair
’ these operations.
I
Department of Housing and Urban Development
The Department can make grants under the Urban Mass Transportation Act of 1964 for capital
expenditures for emergency facilities which may include power supply for the movement of trains,
radio communications equipment, station lighting
and alarm signals. The Department is also able to
provide funds for standby electric generating facilities under its Public Works Planning Advance, Public Facility Loans, and Water and Sewer Grant
programs.
Office of Emergency Planning
Under its national security responsibility for coordinating overall emergency preparedness, OEP,
assisted by the Business and Defense Services Administration of the Department of Commerce, prepared and distributed the questionnaire shown in
figure D-l to a sample group comprising approximately 3000 establishments. Information was requested relative to the effects of the power outage
Standard Industrial Classifications: paper and allied products; chemicals and allied products; stone,
clay and glass products; primary metals industry;
fabricated metal products; machinery, except electrical; electrical machinery; transportation equipment, instruments and related products. Approximately 43 percent of the addressees responded to the
questionnaires. No significant differences were noted
among the responses within a given industrial classification or across industry groups. The responses
indicated that:
1. Production time was lost by those companies
using night shift.
2. Relatively minor damage to equipment was
incurred by firms operating at the time.
Similarly, some work in process was damaged.
.3. On the whole, losses were nominal, although
severe cold weather and longer duration of the
outage would have aggravated the losses.
4. Nearly all reporting companies indicated lack
of sufficient auxiliary generating equipment to
operate independently of commercial power.
Very few companies reported plans to install
auxiliary generating equipment.
5. About one half of the companies in each
classification have emergency shutdown procedures which helped alleviate damage.
6. Available communications were generally
adequate. Telephones were operable and battery-powered radios were in prevalent use.
Teletypes generally were inoperable.
7. Some respondents suggested prompt notification by electric utility via radio, or utility-tocustomer private line regarding magnitude of
outage and probable duration, in order to expedite critical management decisions.
8. Restoration of electric power service, where
possible, should be on a priority basis.
Ii
B”DOBT .e”REA” NO. 97-660,
APPROVAL, EXPIRES /“NE SO.1966
. l.Do
Return no later than
APRIL 22, 1966
Name of Company Reporting
REPORTON EFFECTSOF POWERFAILURE
NOVEMBER 9 AND 10, 1965
b. If y
3-s
?eturn to: U.S. Department of Commerce
Washington, D.C. 2GPO
kttention: Business and Defense Services Administration
Industrial Mobilization (6140)
FILE COPY
. 1.D.a
2. wet
INSTRUCTIONS
hailing - Prepare and teturn one copy of this report to the
Business and Defense Services Administration, Industrial
Mobilization (6140), U. S. Department of Commerce,
Washington, D.C. 20230, no later than April 22, 1966.
2uesti ons concerning the form should be addressed to the
lonstruction, Production and Power Resources Division,
Office of Emergency Planning, Washington, D.C. 20504,
relephone: Area Code 202 - DU 2-2311.
File Copy - In addition to the original report form to be
returned to us, there is enclosed a file copy for your
records. You ate not legally required to fill out ot retain
this file copy- While it would be a convenience to the
Government for a file copy to b e made and retained for
reference purposes, no assurances can be provided that
file copies ate exempt from compulsory examination or
production pursuant to legal process.
3. If L
4. Ifw
5. Do
l 1. 1. Wh
Te
‘lant Address
Ra
TC
or
4. 1. Did your commercial electric power fail?
[? Yes
CIiNo
o. If “Yes,” how long did the failure last?
What was the damage to equipment ot work in process?
2. we
E. Plea.
to en
Was plant operation affected in any other way? Explain
b. If “No,” in your judgment what damage would have been caused by such failure to equipment, facilities, ot work in process?
Explain:
Ceftific
2. How soon would power have to be restored in order to avoid damage mentioned above?
3. Would the effects be different between day or night, and under severe weather conditions? Explain:
FIGURE
176
D-l.-Questionnaire used by Business and Defense Services Administration.
a. Front side
tion co
Nameo
B- 1. Do you have auxiliary generating equipment?
o. If “Yes,” was it put into serviceduring blackout?
If a. above is Yes, what portion of total load can this
auxiliary equipment carry?
0 Yes
ON*
0 Yes
ON*
Hew long can you operate on auxiliary power?
b. If you do oat have auxiliary equipment. are you planning to install such?
.lf so, what portion of your total load would this carry?
0 Yes
0 Yes
ON*
2. Were they used in the blackout?
0 Yes
ON*
3. If so, did their use mitigate damage?
r-J Ye.9
ON*
0 Yes
ON*
C- 1. Do you have emergency shut-down procedures?
ON*
How long could you operate on it?
4. How much rime is required for their execution?
5. DIJ these procedures rely on the use of electric power?
D. 1. Whet communications remained operative during the power failure?
Telephone
0 Yes
IIN*
Radio
0 Yes
ON*
Teletype
0 Yes
ON*
Orher (~eecrw.e)
2. Were the communications available to you adequate during the emergency?
OYCS
ON”
E. Please discuss any observations or recommendations you may have concerning the November 9 outage which might be pertinent
to emergency preparedness.
lame of persoo who should be contacted if questions arise regarding this report
Tel,ephone No. and Atea Code
htificmtion - The undersigned company and the official executing this cenificarion in its behalf hereby certify that the informatioa contained in this report is correct and complete to the best of their knowledge and belief.
Signature of authorized official
q*me of compnny
4ddress of company
FIOURE D-l.-Questionnaire
Title
Dare
used by Business and Defense Services Administration.
b. Reverse side
177
Data based on questions similar to the BDSA
Survey, forwarded to the OEP by the Office of
Minerals and Solid Fuels, Department of the
Interior, indicated that the power outage effects on
coke plants, coke docks, mines and mineral processors in the Northeast were negligible.
OEP requires a rapid and reliable procedure for
gathering information on emergency situations.
Such a system for reporting electric power failures
was developed by the Commission in conjunction
with OEP which will provide information on the
cause and extent of the trouble, restoration problems and schedules, and possible government
actions.
In addition, OEP has taken steps which will improve its ability to respond to this type of significant
incident through additions to its communications
systems and expansion of its automatic staff reporting system.
navigational aids at the Kennedy and LaGuardia
airports; (3) to provide additional portable lights
at various Port Authority facilities; (4) to institute
corrective action and inspection procedures to insure prompt operation of all existing emergency
generators; and (5) to update all existing evacuation and emergency procedures for Port Authority
facilities. The Authority also prepared a report on
long-range plans for providing emergency generators or trickle charge batteries for moving stalled
elevators, power for essential lighting at all Port
Authority facilities, minimum heating in certain
critical areas, radio transmitters where needed to
improve system communications, and electrically
driven compressors for use in certain tunnel pumping operations. Emergency electrical generating
facilities existing or presently scheduled l for instaJlation by the Port of New York Authority are
shown in table D-2.
Department of Agriculture
City of New York
Survey questionnaires were also distributed by the
Department of Agriculture to approximately 200
food processors and handlers. Approximately 50
percent responded, indicating that some nominal
losses were sustained, due mainly to the interruption
of production, cost of idle and standby labor, and
clean-up. Equipment damage was minor. Favorable
weather conditions and off-shift time of day were
contributory factors to keeping the losses small.
Among the many emergency power supply needs
highlighted by the power failure in the City of New
York was the relatively high ratio of hospitals
found to be without reliable auxiliary power-more
than half. As a result of the November 1965 experience, additional rules and regulations pertaining to
emergency lighting and power requirements for all
hospitals and nursing homes were promulgated in
1966 by the City as follows:
National Aeronautics and Space Administration
Hospitals
This agency’s field centers are carrying out a program of updating standby power capability for communications and control to insure uninterrupted
service during all critical phases of major space
flight missions. In addition, improved operation and
maintenance procedures are being implemented to
insure operational readiness of all NASA emergency power facilities.
Port of New York Authority
This agency, responsible for the operations of
certain commuter train service, bridges, tunnels,
airports and terminals in the Metropolitan area of
New York City, reported that actions had been instituted : ( 1) to expand the Port Authority network
of radio communications; (2) -to cooperate with
FAA in the installation of emergency power for
178
The following rules and regulations pertain to
emergency lighting and power requirements for all
existing and new hospitals in New York City.
Purpose :
The regulations set forth herein recognize the dependence of hospitals on electrical power essential
to the safety of the patients and staff, for lighting,
operation of plant and apparatus, and the continuation of the treatment in which timing is critical. These are minimal requirements to achieve,
generally, these ends. Each institution must evaluate
its own plant on the basis of its own program.
Nothing in these regulations is to be construed as
precluding expansion of emergency electrical SYSterns to other areas or functions.
1 Schedules received April 7,1967.
John F. Ken
Proposel
Swih
Polic
Obst
HZ
Existing
Swit
Rem
Ren:
Rtlr
ReIX
ASE
oub
ARE
Poli
Bull
La Guardia
Propose
Fiel
Cer
F:
Cer
F
Cer
F
Gel
F
PO1
Ha
M2
Ob
I
Unit
--
-John F. Kennedy International Airport:
proposed:
Switchhouse No. 1. . . . . . .
Area served
. 3 0 0 K W . . . . . . . . . . . . . . 1Runway, Taxiway,
Obstructions at Various Locations
Hangars, Poles, etc.
Centerline & Edge
Ltg.
150 KW . . . . . . . . . . . . . 1 Entire Garage, l/3 Apron
Field Ltg.
3 5 0 K W . . . . . . . . . . . . . 1 Emerg. Ltg., Fire Alarm
Supv. office, Obstruction Lts.
ZOKW . . . . . . . . . . . . . . . !Sewage Ejector, Controls
& Emerg. Ltg.
,Obstruction Ltg . . . . . . . .
Approx. 15 KW in
smaller units.
W:
Switchhouse No. 1. . . . . . . . . . . .
125 KW (F.A.A.) . . . . . . 1Runway, Taxlway Ltg. .
Police Emergency Garage.. . . . . . .
International Arrivals Building. . .
IAB-Sewage Ejector Bulldlng. . . .
Remote Site No. 1.. . . . . . .
Remote Site No. 2. . . . . . . . .
Remote Site No. 3. . . . . . . . . . . . .
75 KW (F.A.A.). . . . . . . IControl Tower Navigational Aids.
25 KVA (F.A.A.). . . . . 1 Ground & Air. . . . .
25 KVA (F.A.A.). . . . . 1 Radio Control. . . . . . . .
Transmit & Receive. . .
25 KVA (F.A.A.) . . . . .
Remote Site Vortac (Radio Beam),
37.5 KVA (F.A.A.). . . . 1Navigational Aid. . . . .
ASR-4 Site (Approach Radar).
62.5 KVA (F.A.A.). . . . 1Navigational Aid. . . . . . .
Outer Marker Site (Navigation Ald
8 KVA (F.A.A.). . . . . . .
Navigational Aid. . . . . .
ARSR-2 (Long Range Radar). . .
125 KVA (F.A.A.). . . .,.
Navigational Aid. . .
Police Emergency Garage. . . . . .
35 KW (Mobile). . . . .
Entire Garage.. . . . . .
25 KW . . . . . . . . . . . . . . .
Emerg. Ltg. & Power.. .
288KW . . . . . . . . . . . . . .
Runway, Centerline,
Edge & Taxiway Ltg.
Switchhouse No. 1. . . . . . . . . . .
Building No. 141.. . . . . . . . . . . . . .
La Guardia Airport :
Proposed :
Field Lighting Vault. . . . . . . . . . .
Central Terminal Building,
Finger # 1
Central Tuminal Building,
Finger #2
Central Terminal Building,
Finger #3
Central Terminal Building,
Finger 14
Police Emergency Garage. . . . .
Hangar No. 7B. . . . . . . . . . .
I
Scheduled
colxlmkioning
March 1868.
March 1868.
March 1868.
March 1868.
March 1868.
,‘/j
To be returned to FAA
&rcpiacalby300
KW unit.
To be replaced by a 588
KW FAA Gen.
Fed from 500 KW Gen.
Fed from 500 KW Gen.
To remain FAA owned
82 operated.
To remain FAA owned
& opcratcd.
To remain FAA owned
& opaatal.
To remain FAA owned
& operated.
To remain FAA owned
& operated.
To be replaced by a
158 KW unit.
Mobile Unit.
March 1988.
75KW. . . . . . . . . . . . . . .
Emerg. Ltg., Fingers,
Wing & Central Bldg.
s of Apron Field Ltg.,
Sewage Ejectors, Air
Comp. & Emerg. Ltg.
in Heating Plant.
150 KW . . . . . . . . . . . .
150 KW . . . . . . . . . . . . .
200KW.. . . . . . . . . . . .
6OKW . . . . . . . . . . . . .
25KW . . . . . . . . . . . . .
Marine Terminal.. . . . . . . . .
25KW.. ...........
Obstructions at Various Location
Dike Pump Houses, Hangars, Etc
Approx. 30 KW. . . . . .
4
rIMarch 1868.
Entire
Garage.
.
.. March 1868.
March 1868.
Emerg. Ltg., Fuel
Pumps, Sewage
Ejector.
Emcrg. Ltg., Obstructior L March 1968.
Lts., Sewage Ejector.
Obstruction Lights. . . . .. March 1868.
il
TABLE
D-2.-Port of N~ZII York Authority Emergcncy Electrical Power Equipment-Continued
Area served
La Guardia Airportaontinued
Existing :
Control Tower. . . . . . . . . . . . . . .
125 KVA (F.A.A.). . .
Field Vault. . . . . . . . . . . . . . . .
75 KVA (F.A.A.). . .
Control Tower Navigational Aids.
Taxiway & Runway Ltg.
Police Emergency Garage. . . . . .
32 KVA . . . . . . .
Entire Garage.. . . . .
Central Terminal Building. . . . . .
ASR-4 Site (Approach Radar). . . .
28 KVA (Mobile). . . .
75 KVA (F.A.A.). . .
Outside Lighting. . . . .
Navigational Aids. . . . .
ATR Site (Radar). . . . . . . . . . . .
25 KVA (F.A.A.). . . .
Navigational Aids. . . . .
Wave Guide Local&r Site.. . . . . .
37.5 KVA (F.A.A.). . .
Navigational Aids. . . . .
Newark Airport :
Proposed :
Switchhouse. . . . . . . . . . . . . . . . .
5OOKW.............
Police Emergency Garage. . . . . . . .
5OKW.. . . . . .
Terminal Building. . . . . . . . . . . .
75 KW . . . . . . .
Terminal
Existing :
Building.
.
.
. .
Various Locations. . . . . . . . . . .
Field Lighting Vault. . . . . . . . .
Port Authority Building:
Proposed :
Basement. . . . . . . . . . . . . . . . . . . . . .
8th Avenue Basement. . . . . . . . . . .
Existing:
Switchboard J. . . . . . . . . . . . . . . .
Center Basement. . . . . . . . . . . . . .
Switchboard I . . . . . . . . . . . . . . . . .
Bus Terminal:
Proposed : Mobile Unit. . . . . . . . . . . .
Edge, Center Line,
Emerg. Htg. & Ltg. &
FAA Loads to 250 KW
(Required by FAA)
Entire Garage, Obstruction Lts.
1Emerg. Ltg., All Facility
Radio-Partial Apr.
1 KW.
Ltg. 1Obstruction Ltg. . . . . . . .
SKW......
2-25KW...
2-5OKW...
I-15KW...
.
.
1
.
2-5KW..
5KW....
5KW....
New York Truck Terminal: Existing . . . . . .
Hoboken Piers : Existing. . . . . . . . . . . . . . . .
5KW....
5KW....
Port Newark: Existing.. . . . . . . . . . . . . .
2-5 KW..
January 1968.
January 1968.
NCW
Lincoln Tunl
Proposed
George Wasl
Proposed
Adm
Mair
Palis;
ing
Bayonne BrL
Existing:
Outerbridge
Existing:
January 1968.
January 1968.
December 1967.
December 1967.
Port Authol
proparsd
33rx
23~
14t1
9th
ChI
Exe
Gra
December 1967.
. .
. 1Elevator 8th Ave.,
Emerg. Ltg.
. 1Htg., Emerg. Ltg.. . . .
. IElec. Htg.-Steam PlantEmerg. Ltg.
1Emerg. Ltg. . . . . . . . . . .
. 1Boiler Room Power Base
Gravity Tank.
1Mobile Units-Emerg.
Power & Light.
December 1967.
...
...
Holland Tun
Proposed
N-V.
Gocthals Brif
Existing:
,Stairway Ltg.. . . . . . . . .
. 1Lighting. . . . . . . . . . . . .
,Stairway Ltg.. . . . . .
70 KW
.
To remain FAA installed & operated.
To remain FAA installed & operated.
To remain FAA installed & operated.
...
...
. .
50 KW
100 KW.
FAA maintained to
remain.
FAA Generator to be
replaced ‘by 200 KW
unit.
To be replaced by 60
KW unit.
IMobile Units. . . . . . . . . .
1Mobile Units.. . . . . . . . .
Mobile Units.. . . . . .
1Runway Lighting. . . . . . .
50KW.. . . . . . . . . . . . . . 1Emerg. Ltg., Elevator. . .
10 KW . . . . . . . . . . . . . . . . 1Replace Existing 5 KW
Unit.
Existing: Basement . . . . . . . . . . . . . . . .
Bus Station:
Proposed: Near Switchboard. . . . . . .
180
. Runways, Taxiway,
Scheduled
Commissioning
Being replaced.
Pav
HOI
Hu
Jm
Wa
Emagmcy
Existin!
Pot
Get
Go
TABLE D-2.-Port of Nczu York Authority Emergency Electrical Power Equipment-Continued
-
Unit
Area served
Holland Tunnel:
Proposed :
New Jersey Administration Building
30KW.. . . . . . . . . . . . .
New York Field Office. . . . . . . . . . .
15KW. . . . . . . . . . . . . .
Emerg. Ltg., Htg., Tolls
Indication.
Emerg. Ltg., Htg., Tolls
Indication.
Lincoln TUMC~:
Proposed : Administration Building. . . .
55KW. . . . . . . . . . . . . .
Emerg. Ltg., Htg., Tolls
Indication.
December 1967.
George Washingtog.Bridge:
Proposed:
Administration Building. . . . . . . . . .
55KW. . . . . . . . . . . . . .
December 1967.
Main Plaza Building . . . . . . . . . . . . .
30KW.. . . . . . . . . . . . .
Palisade-s Interstate Parkway Build.
ing.
Bayonne Bridge:
Existing: Field Office. . . . . . . . . . . . . . . .
30KW. . . . . . . . . . . . . .
Emerg. Ltg., Htg., Tolls
Indication.
Emerg. Ltg., Htg., Tolls
Indication.
Emerg. Ltg., Htg., Tolls
Indication.
--
150KW . . . . . . . . . . . . .
Emerg. Ltg., Htg., Tolls
Indication.
Goethals Bridge:
Existing: Electric Shop. . . . . . . . . . . . . .
150KW. . . . . . . . . . . . .
Emerg. Ltg., Htg., Tolls
Indication, Base Radio.
Outerbridge:
Existing : Garage. . . . . . . . . . . . . . . . . . . .
60KW. . . . . . . . . . . . .
Htg., Emerg. Ltg.,
Tolls Indication
PORTA
Scheduled
Commissioning
Dtrcember 1967.
December 1967.
Decemba 1967.
December 1967.
E UNITS 1.5 KW, 1.8 KW, 3.5 KW, 5 KW
-
Port Authority Trans-Hudson:
Proposed:
33rd Street. . . . . . . . . . . . . . . . . . . . .
23rd Street. . . . . . . . . . . . . . . . . . . . .
14th street. . . . . . . . . . . . . . . . . . . . .
9th Street. . . . . . . . . . . . . . . . . . . . . .
Christopher Street. . . . . . . . . . . . . . .
Exchange Place. . . . . . . . . . . . . . . . .
18 Battery Units. . .
12 Battery Units. . .
8 Battery Units..
4BatteryUnits....
4BatteryUnits....
12 Batte-ry Units.. .
Grove Street. . . . . . . . . . . . . . . . . . . . .
Pavonia Street. . . . . . . . . . . . . . . . . . .
Hoboken Terminal. . . . . . . . . . . . . . .
Hudson Terminal . . . . . . . . . . . . . . . . .
Journal Square. . . . . . . . . . . . . . . . . . .
Washington Street Sub. . . . . . . . . . . .
6 Battery Units . . . . . . . .
6 Battery Units . . . . . . . .
17 Battery Units . . . . . . .
34 Battery Units . . . . . . .
27 Battery Units . . . . . . .
500 KW . . . . . . . . . . . . . .
Emergency radio system:
Existing :
Port Authority Building. . . . . . . . . . .
‘,
1.5 KVA.. .
George Washington Bridge . . . . . . . . .
300 Watts. . . .
Goethals Bridge. . . . . . . . . . . . . . . . . .
300 Watts. . . . . . . . .
Lighting . . . . . . . . December 1967.
Lighting. . . . . . . .
Do.
Do.
Lighting. . . . . . . .
Do.
Lighting. . . . . . . .
Do.
Lighting. . . . . . . .
Lighting . . . . . . . . . Partial October ‘67,
completed December
‘67.
Station Lighting. . . . . . . . .
Do.
Station Lighting. . . . . . . . .
Do.
Do.
Station Lighting. . . . . . . . .
Do.
Station Lighting. . . . . . . . .
Do.
Station Lighting . . . . . . . . . .
November 1967.
Tunnel Ltg. &
Compressors
Station
Station
Station
Station
Station
Station
Power Supply for “D” &
“ES, & Cbn “A”
Control Station
Power Supply for Chan.
“A” Station
Power Supply for than.
“A’ Station from
Facility Gen.
-
181
General Requirements :
Emergency lighting and power shall be provided
from an auxiliary source generated on the hospital
premises. The auxiliary source shall have a capacity
sufficient to supply and maintain the total connected
emergency lighting and power load, with not more
than six (6) percent reduction from rated system
voltage for a continuous period. Each receptacle
shall be computed at no less than two hundred
(200) watts. Fuel capacity shall be provided for a
period of at least twenty-four (24) hours with the
generator operating at maximum capacity. Means
shall be provided for automatically transferring the
emergency lighting and power supply from the main
source to the auxiliary source within fifteen (15)
seconds in the event of a failure of the main source.
The emergency power system shall be tested once a
week.
When the primary source of current for the building is supplied by a generating plant on the premises, an emergency supply shall be obtained from
a source other than the primary source.
Emergency lighting shall be provided for the
following spaces, with the load being automatic-
ally transferred :
a. All lighting outlets in operating rooms, delivery rooms, exit signs, and stairways.
b. Lighting outlets in labor rooms, nurseries, recovery rooms, emergency rooms, intensive care
units, anesthetizing areas, essential clinical
laboratories and radiological facilities, blood
bank, and nurses’ stations; .to provide. average
illuminating intensity of not less than fifteen
( 15) foot candles.
c. One-half ( f/2 ) the lighting units in main pharmacy, telephone switchboard rooms, main
switchboard rooms, transformer rooms, boiler
rooms, machine rooms containing emergency
equipment, and generator set location.
d. Safety lighting for corridors, laundry (for new
hospital construction only), kitchen, and
utility rooms; provided that the average illumination intensity of the safety lighting is not
less than five (5) foot candles.
Emergency power shall be provided for the following, and the load shall be automatically trans-
ferred :
a. One ( 1) elevator which services inpatients on
each occupied floor. The wiring shall be arranged to permit connecting all the elevators
to an emergency source, with controls arranged to operate one ( 1) elevator at a time.
182
b. Two (2) identified receptacles in each operating, recovery, delivery, and emergency room,
intensive care unit, all nurseries, anesthetizing
area, and essential critical laboratories.
c. Identified receptacles spaced throughout all
corridors in all nursing units so that a onehundred (100) foot extension cord can provide emergency power to every bed. Extension cords shall be provided in readily available
locations.
d. Nurses’ call system; physiological monitoring
systems; paging system; telephone switching,
signaling, and monitoring equipment; and
other essential communications equipment.
e. All power plant and electrical equipment necessary for the continuous operation of:
1. One ( 1) diagnostic radiographic x-ray unit
and related processing and viewing facilities.
2. Fire pump.
3. Alarm system for: fire, sprinkler, fire and
smoke detection, generator unit malfunction, medical gases, and other alarm systems
mandatory by local ordinance.
4. Central suction and medical air compressors.
Emergency power shall be provided for the following, and the load may be either automatically
or manually transferred :
a. Fuel burning equipment including heaters,
pumps, fans, and controls. Where electricity
is the only source of power normally used for
space heating, the emergency service shall
provide for heating of operating, labor, recovery, intensive care, nurseries, and patient
rooms. Emergency heating of patient rooms
will not be required if the hospital is supplied
by at least two utility service feeders, each supplied by separate generating sources.
b. All pumps; sumps, boiler feed, domestic water,
sewerage and ejector systems.
c. Air compressors for general building use.
d. Refrigeration for blood and bone banks,
pharmaceuticals, frozen foods, and other critical refrigeration.
e. Ventilating systems for one ( 1) operating
room, one ( 1) delivery room, one ( 1) emergency room, and all nurseries.
f. Data transmission’equipment used for diagnostic or other purposes related to the care or
treatment of patients.
Enforcem
The efl
ulations sl
a. New
Imn
tracl
196t
b. Exis
Buil
shal
N&sing I
The fo
Emergent
and New
General 1
Emergt
room, exi
and nurs
be suppli
or a battc
ity suffic
emergent
(4) hour
shall be
hours. Tl
available
tamed ir
regulatio
sion of z
Unit Eql
Unit f
in lieu 0;
Individu
nation sl
tery cha
(d) a :
lamps 511
ply to tl
able rati
not less
total lan
of at lea
of the a
strutted
service.
in place
shall hz
cordanc
permitt
by flexi
at
Enforcement:
The effective date for compliance with these regulations shall be as follows :
a. New Building:
Immediately, except that projects under contract on July 1, 1966 shall have until July 1,
1968 to comply.
b. Existing Building:
Buildings constructed prior to July 1, 1966
shall have until July 1, 1968 to comply.
N&sing Homes
The following Rules and Regulations pertain to
Emergency Lighting Requiremeilts for all Existing
and New Nursing Homes in New York City.
General Requirements :
Emergency lighting shall be provided for boiler
room, exits (including exit signs), patient corridors
and nurses’ stations. Such emergency lighting shall
be supplied by an automatic emergency generator
or a battery on the premises, and shall have a capacity sufficient to supply and maintain the total
emergency lighting load for a period of at least four
(4) hours. Fuel storage capacity for the generator
shall be adequate for a period of at least four (4)
hours. This emergency lighting shall be immediately
available when required and continuously maintained in proper working order. Nothing in these
regulations is to be construed as precluding expansion of emergency lighting systems to other areas.
Unit Equipments :
Unit equipments of approved type may be used
in lieu of the methods specified in paragraph 112.1.
Individual unit equipments for emergency illumination shall consist of (a) storage battery, (b) battery charging means, (c) one or more lamps, and
(d) a relaying device arranged to energize the
lamps automatically upon failure of the normal supply to the building. The batteries shall be of suitable rating and capacity to supply and maintain at
not less than 91 per cent of rated lamp voltage the
total lamp load associated with the unit for a period
of at least four (4) hours. Storage batteries whether
of the acid or alkali type shall be designed and constructed to meet the requirements of emergency
service. Unit equipments shall be permanently fixed
in place (i.e. not portable) properly grounded and
shall have all wiring to each unit installed in accordance with one of the approved wiring methods
permitted in Article 5. They shall not be connected
by flexible cords. Emergency illumination fixtures
267-7810-67-13
which obtain power from ;t unit eauinment
and
I I
are not part of the unit equipment shall be wired
to the unit equipment by an approved wiring
method permitted in Article 5.
Approval of Drawings:
Plans and specifications incorporating the extent
of the emergency lighting system to be provided,
details of the equipment to be used and its associated
wiring method shall be submitted in triplicate for
approval to the Commissioner of the Department
of Water Supply, Gas and Electricity, Municipal
Building, Manhattan.
Enforcement:
The effective date for compliance with these
regulations shall be as follows:
a. Proprietary Nursing Homes:
New and existing buildings-Effective immediately.
b. Voluntary Nursing Homes :
New. buildings-Effective immediately.
Existing buildings constructed prior to July
1, 1966 shall have until July 1, 1968 to
comply.
Federally Supported Hospitals
A nationwide study of auxiliary power availability in the Nation’s hospitals as of 1965, based on
Public Health Service staff surveys and findings by
the American Hospital Association, showed that
of 6,915 hospitals, 2,973 or 43 percent had adequate
emergency power. About 35 percent or some 2,420
required auxiliary power upgrading, 22 percent
or some 1,522 needed complete auxiliary power
systems.
All of the agencies queried recognized the need
for auxiliary power equipment, updated emergency
operating procedures and improved emergency
lighting and power systems to maintain essential
services. At the time the FPC query was issued,
many agencies had already initiated actions to implement some of the most critical improvements.
The Federal Hospital Council approved a draft
of new regulations to be promulgated by the Publit Health Service as a basis for granting aid to
hospitals, pursuant to the Hill-Burton Act, Public
Law 725, 79th Congress, as amended. These regulations were approved by the Secretary, Department
of Health, Education, and Welfare on June 9,1967,
and read as follows :
t
Public Health Service Regulations Pertaining to
Emergency Electric Service for General Hospitals.
J. Emergency Electric Service
1. General : To provide electricity during an interruption of the normal electric supply that could
affect the medical care, treatment, or safety of the
occupants, an emergency source of electricity shall
be provided and connected to certain circuits for
lighting and power.
2. Sources: The source of this emergency electric service shall be as follows :
a. An emergency generating set, when the normal service is supplied by one or more central station transmission lines.
b. An emergency generating set or a central station transmission line, when the normal electric supply is generated on the premises.
3. Emergency generating set. An emergency generating set, including the prime mover and generator, shall be located on the premises and shall be
reserved exclusively for supplying the emergency
electrical system. Exception: A system of prime
movers which are ordinarily used to operate other
equipment and alternately used to operate the emergency generator(s) will be permitted provided that
the number and arrangement of the prime movers
is such that when one of them is out of service (due
to breakdown or for routine maintenance), the remaining prime mover(s) can operate the required
emergency generator(s) and provided that the connection time requirements described in sec. 8-2455
are met. The emergency generator set shall be of
sufficient kilowatt capacity to supply all lighting and
power load demands of the emergency system. The
power factor rating of the generator shall be not less
than 80 percent.
4. Emergency electrical connections. Emergency
electric service shall be provided to circuits for lighting and for operation of equipment as follows :
a. Lighting :
( 1) Exitways and all necessary ways of approach thereto including exit signs and
exit direction signs, exterior of exits,
exit doorways, stairways, and corridors.
(2) Surgical, obstetrical, and emergency room
operating lights.
(3) Nursery, laboratory, recovery room, intensive care areas, nursing station, medication preparation area, and labor rooms.
(4) Generator set location, switch-gear location, and boiler room.
184
b. Equipment: Essential to life, safety and for
protection of important equipment or vital
materials :
( 1) Nurses’ calling system.
(2) Alarm system including fire alarm actuated at manual stations, water flow alarm
devices of sprinkler system if electrically
operated, fire detecting and smoke detecting systems, paging or speaker systems if intended for issuing instructions
during emergency conditions, and alarms
required for nonflammable medical gas
systems, if installed.
(3) Fire pump, if installed.
(4) Receptacles for incubators for infants.
(5) Pump for central suction system.
(6) Sewerage or sump lift pump, if installed.
(7) Receptacles for blood bank refrigerator.
(8) Receptacles in operating, recovery, intensive care, and delivery rooms except those
for X-ray. At least one duplex receptacle
in each nursery.
(9) Duplex receptacles in patient corridors.
One elevator, where elevators are used
to transport patients to operating and delivery rooms or from these rooms to nursing areas on another floor.
Equipment such as burners and pumps
necessary for operation of one or more
boilers and their necessary auxiliaries and
controls, required for heating and sterilization.
Ventilation of operating and delivery
rooms.
Equipment necessary for maintaining
telephone service.
(14) One electric sterilizer, if installed.
c. Heating: Where electricity is the only source
of power normally used for space heating, the
emergency service shall provide for heating of
operating, delivery, labor, recovery, intensive
care, nurseries, and patient rooms. Emergency
heating of patient rooms will not be required
under either of the following conditions : ( 1)
the design temperature is higher than + 20”F.,
based on the Median of Extremes as shown in
the current edition of the ASHRAE Handbook of Fundamentals; or (2) the hospital is
supplied by at least two utility service feeders,
each supplied by separate generating sources,
or a network distribution system fed by two or
more generators, with the hospital feeders so
route
any
pita1
mart
5. Deti
be so co
normal e
brought tc
within l(
automatic
ing; all z
ment net
pump for
operating
covery r(
nurseries.
to .be con
be connec
automatif
quently
manual 1
to the c
marked f
lights, PI
ing or fo
of transfc
terruptio
be used
generatoi
site, the
hour ope
ground tl
storage f;
Federal
The v
with the
a nation;
Congress
projects,
visory co
The S
15, 1966
govemm
try to a
of the N
mittee tc
of Repr
Foreign
’ Senate
printed IV
routed, connected, and protected that a fault
any place between the generators and the hospital will not likely cause an interruption of
more than one of the hospital service feeders.
’ 5. Details: The emergency electrical system shall
be so controlled that after interruption of the
normal electric power supply, the generator is
brought to full voltage and frequency and connected
within 10 seconds through one or more primary
automatic transfer switches to all emergency lighting; all alarms; blood banks; nurses’call; equipment necessary for maintaining telephone service;
pump for central suction system; and receptacles in
operating and delivery rooms, patient corridors, recovery rooms, intensive care nursing areas, and
nurseries. All other lighting and equipment required
to be connected to the emergency system shall either
be connected through the above described primary
automatic transfer switching or shall be subsequently connected through other automatic or
manual transfer switching. Receptacles connected
to the emergency system shall be distinctively
marked for identification. Storage-battery-powered
lights, provided to augment the emergency lighting or for continuity of lighting during the interim
of transfer switching immediately following an interruption of the normal service supply, shall not
be used as a substitute for the requirement of a
generator. Where fuel is normally stored on the
site, the storage capacity shall be sufficient for 24hour operation. Where fuel is normally piped underground to the site from a utility distribution system,
storage facilities on the site will not be required.
Federal legislative Proposals
The vital concern of the Federal Government
with the reliability of bulk electric power supply on
a national scale is expressed in legislative proposals,
Congressional hearings, studies, reports, research
projects, and the activities of special technical advisory committees.
The Senate Committee on Commerce, on March
15, 1966, issued an interim report 1 on responses by
government (Federal, State and local) and industry to a series of pertinent questions on the impact
of the November 9th outage. The Special Subcommittee to Investigate Power Failures of the House
of Representative’s Committee on Interstate and
Foreign Commerce held hearings on the November
* Senate Report No. 1079, 89th Congress, 2d Session,
March 22, 1966.
printed
power interruption on December 15,1965 and February 24 and 25,1966.
Measures directed towards mitigating the possible
adverse affects of power failures on hospitals were
introduced under S. 2803, H.R. 12841 and H.R.
16050 during the 89th Congress, 2d Session, and
H.R. 6260 of the 90th Congress. These bills would
amend the Public Health Service Act to provide
grants and loans for the construction and improvement of standby electrical systems for public or private non-profit hospitals.
S. 3004 introduced during the 89th Congress and
S. 536,9Oth Congress, would require specified buildings such as hotels, motels, train and bus stations,
and airports, restaurants and similar public gathering places to be equipped with emergency lighting
systems.
State legislative Proposals
The Northeast power failure alerted every section of the country to the possibility of a similar
occurrence affecting their power systems and the
populations they serve. Consequently, many states
and independently, electric utility companies, have
initiated studies to determine the probabilities for
such failures within their systems and the necessary
corrective measures.l The National Association of
Railroad and Utility Commissioners has communicated with all state utility regulatory agencies requesting that comprehensive investigations be made
of power systems within their jurisdictions and that
appropriate actions be taken by the state commissions.
An example of a state’s concern is a California
study 2 of six large California utilities. The study
indicated that 2305 customers had installed standby
generating equipment to provide for their minimum needs in the event of a power failure. These
customers were classified as follows:
Hospitals and Medical Centers---------------Communications --- ____- - ______ --- ____ -----Police, Fire, and Other Governmental Functions-Military -_---__- ________ --__--- ____________
Transportation (including navigation facilities) --Other (including commercial and industrial)----
596
476
690
124
77
342
2,305
‘See Part 2, Northeast Power Failure, Addendum to
Hearings, Special Subcommittee to Investigate Power
Failures, Committee on Interstate and Foreign Commerce,
House of Representatives.
*California Systems Reliability Task Force Report to
Public Utilities Commission Staff, December 28, 1965.
The California experience is fairly representative of the national attitude towards the need for
this critical equipment.
A state-by-state survey by the Engine Generator
Set Manufacturers Association, Chicago, Illinois,
of mandatory provisions for standby power for essential services indicates that nationwide, much
remains to be done. As shown in table D-3, of the
51 states (including the District of Columbia), 22
have no legislative provisions for any emergency
power, while the remaining 29 have some legislation or policy relating to emergency power for some
--
Legislation Requiring Emergency
Power.
/
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Types of Buildings and/or Installation
Sites Covered.
For Lights Only (L)-Light and
Power (P).
essential services. The kinds of emergency power to
be provided vary and include battery-powered
lights, generator sets, and alternate feeder lines. In
several states, no particular power source is specified. A wide range of buildings or installations is
covered by the meager legislation in these 29 stateshospitals, nursing homes, schools, theaters and public gathering places, airports, public buildings, hotel
and office buildings. Six states include only one of
these types of installations or buildings; the remainder includes from two to five such types. Eleven of
the 29 states require auxiliary electricity for lights
r
-
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Codes and Regulations
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7
- - - - - - *= Although Nevada has no legislative requirement for
2=Department of Licenses and Inspections.
emergency power in public buildings, Nevada reports that
3= Advisory Board.
it is the policy of the State Planning Board to install emer4=Department of Public Safety.
gency power and lighting facilities in all state financed
5=Fire Marshal.
public buildings and to encourage this for non-state owned
6=Department of Public Buildings.
public buildings.
7=State Board of Health.
#=Based on survey by Engine Generator Set Manufac8=Department of Labor and Industries.
turers Association.
9=Not Specified.
Information as of April 1, 1967.
186
Y Y
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s S
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A J
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7
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only, wh
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29 states,
in the Sta
share this
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and Insp
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B= Nur
C= Sch
D=Th(
E=Offi
F=Hot
G= Air]
only, while 19 states require electric energy for
other power uses as well as lights. Codes and regulation enforcement authority also vary. In 15 of the
29 states, responsibility for compliance resides within the States’ Boards of Health. Fire marshalls either
share this responsibility or are solely responsible in
eight states. In the remaining seven states this duty
falls within the purview of Departments of Licenses
and Inspections, Buildings, Public Safety or Labor
and Industries.
Since the November 9, 1965, power outage, utilities and other entities involved with essential servfor Emergency Power #
-
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7 3
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8
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A= Hospitals.
B=Nursing Homes.
C= Schools.
D=Theaters and Public Gathering Places.
E= Office Buildings
F=Hotels and Apar 1ment Buildings.
G= Airports.
4
&
2
-iz
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ices in the Northeast-and their nationwide counterparts-have greatly improved their readiness
and capability for preventing power failures and
for dealing rapidly with major failures should they
occur. Their actions focus on correcting system deficiencies such as those which caused or contributed
to the November 9 interruption. Present plans provide for the improvement and strengthening of
interconnections with neighboring systems, the installation of auxiliary power units to assure the
availability of critical power, improvement and
greater reliability of communications, and updating
operating instructions and procedures.
H= Fire and Police Stations.
J= All Public Buildings, State and Commercial.
K= State Buildings only.
Q=Battery Powered Lights.
R= Emergency Generator Sets.
S=Alternate Source of Electricity from another Feeder.
T= None specified.
187
APPENDIX E
SUMMARY OF LARGER POWER INTERRUPTIONS 1954-1967
In the period 1954-1966, there were.148 power
interruptions which were sufficiently important to
gain publicity. Some of these involved transmission
network instability and separation; others were
local in nature, affecting load areas served radially
from the network. A summary of these interruptions is presented in table E-l, and their locations
are shown on figure E-l.
FPC Order No. 331, issued December 20, 1966,
requires all entities engaged in the generation and
transmission of electric power to report significant
interruptions of bulk power supply to the Commission.
Through June 12, 1967, fifty-two power interruptions were reported in accordance with Order
No. 331. These are briefly described below.
Marias River Electric Cooperative, Inc., January
15; 1967
Failure of a suspension insulator during a blizzard
resulted in interruption to Shelby, Rudyard, Cut
Bank, and Tiber Dam substations in Montana.
Service to some 6,900 customers amounting to about
19,000 kilowatts was interrupted for times ranging
from one hour and 43 minutes to nine hours and
13 minutes.
Moreau Grand Electric Cooperative, January 16,
1967
This outage affected about 3,000 customers and
4,000 kilowatts of load in an area of some 5,000
square miles around Timber Lake and Eagle Butte,
North Dakota. The outage occurred on a 69 kv
line of the U.S. Bureau of Reclamation during a
period of high winds.
Union Electric Company, January 24, 1967
A tornado damaged distribution and subtransmission facilities in northwest St. Louis County,
Missouri, affecting service to about 75,000 customers. Restoration was begun in 35 minutes and
service was restored to all customers who were in a
condition to accept service in about 17 hours.
Provo, Utah, January 25, 1967
Service was interrupted for 20 minutes to the
entire 13,200 customers of the City of Provo. It is
believed that the outage resulted from a short circuit when accumulated snow fell from the conductors.
Grand River Dam Authority, January 26, 1967
Failure of a lightning arrestor interrupted 30,000
kilowatts of load of two industrial customers for
about 30 minutes near Choteau, Oklahoma.
Illinois Power Company, January 26, 1967
About 17,000 customers with a load of 30,000
kilowatts in the Champaign-Urbana area of Illinois
were without power for periods ranging from about
two to six hours. No damaged facilities were found,
and the outage is presumed to have been caused by
high winds and icing conditions.
El Paso Electric Company, January 28, 1967
A bird carrying a metallic necklace caused a short
circuit on the bus of the Sunset substation which
interrupted electric service to commercial loads and
office buildings. About 25,000 kilowatts was interrupted for 55 minutes.
Fulton, Kentucky, Municipal, February 2, 1967
Lightning destroyed two cross arms on a 69 kv
line of the Tennessee Valley Authority, serving the
City of Fulton. 1,640 customers with a load of 960
kilowatts were interrupted for 20 minutes.
Tennessee Valley Authority, February 8, 1967
The failure of a current transformer resulted in
the interruption of about 64,000 kilowatts of load
in Warren and Simpson Counties, Kentucky, including the cities of Bowling Green and Franklin.
All loads were restored in 30 minutes except South
Bowling Green where restoration was further complicated by a frozen valve on the circuit breaker
air suppiy. This service was restored in 64 minutes.
189
Chugach Electric Association, Inc., February 9,
1967
37,500 kilowatts of load and 18,100 customers in
the Anchorage, Alaska, area were interruped for 15
minutes when an air-break switch failed during
tests following repair work.
Moreau Grand Electric Cooperative, February 9,
1967
Loss of a pin on a 69 kv line interrupted power
to some 2,500 customers with a load of about 2,000
kilowatts in the Timber Lake, Eagle Butte, Dupree,
Isabel, and McLaughlin areas of South Dakota for
20 minutes.
Ohio Edison Company, February IS, 1967
High winds blew construction material into the
Cloverdale substation, so severely damaging one of
the double busses that it had to be cut away. Service
to 20,000 customers in Massillon, Ohio, amounting
to 50,000 kilowatts, was interrupted for 55 minutes.
Public Service Company of Indiana, February 17,
1967
Failure of a transformer tap-changer at Batesville, Indiana, caused a short circuit in the primary
winding. An apparent operating error in subsequent
switching actuated a differential relay, leading to
additional checking of the circuits before service was
restored. About 28,000 kilowatts of load and 6,180
customers were interrupted for 33 minutes.
Burbank, California, Municipal, February 20, 1967
A fault on the City of Los Angeles system resulted
in loss of the City of Burbank’s 55 mw generating
unit. Service to 3,000 customers amounting to 10,000
kilowatts was interrupted for 22 minutes.
Carolina Power d Light Company, February 24,
1967
A broken insulator resulted in tripping of a 1151
12 kv transformer at West Asheville, North Carolina
substation. About 16,000 customers and 27,000 kilowatts of load were interrupted for one hour and 52
minutes.
Tennessee Valley Authority, February 25, 1967
A high temperature detector removed a transformer from service at Johnson City, Tennessee.
No damage was apparent and when restored to
service the transformer continued to function normally. Loads of 36,700 kilowatts were interrupted
for 36 minutes.
190
Arizona Public Service Company, February 25,1967
An area in and around the towns of Gila Bend,
Ajo, Pheba, Hyder, Aztec, and Horn in southwestern Arizona were without power for about 29 minutes after a light plane flew through a 69 kv line.
Total load for the 4,500 customers affected was
about 25,000 kilowatts.
Georgia Power Company, February 27, 1967
Service was interrupted to parts of Fulton and
Cobb County, Georgia, including parts of Atlanta,
Smyrna, and Marietta, when an overhead ground
wire fell into a 115 kv line. 56,000 kilowatts of load
were interrupted-20,000 customers for 31 minutes
and the Lockheed-Georgia plant for 43 minutes.
Texas Power t3 Light Company, February 28,1967
An insulator failure at Paine switching station
interrupted the 69 kv bus, including a 138/69 kv
transformer. Subsequent trouble with the transformer breaker prolonged the interruption. 30,000
kilowatts of load to 18,000 customers in a 900 square
mile area around the towns of Bonham, McKinney,
Gainesville, Sherman, and several small communities were interrupted for 33 minutes.
Duquesne Light Company, March 6,1967
Flood-borne debris clogged the cooling water intakes to the Elrama 325 mw generating station,
causing it to be shut down. Ties with other systems
were inadequate and eight industrial customers
curtailed 120 mw of load for a maximum of four
hours and 36 minutes. The area affected was in
Allegheny and Beaver counties in and near Pittsburgh, Pennsylvania.
Pacific Power & Light Company, March 10, 1967
28,000 kilowatts and 6,000 customers in and
around Crescent City, California, were interrupted
from 61 minutes to three hours and 16 minutes. NO
facilities were found to be damaged, and the interruption is believed to have resulted from heavy
snow accumulation on a 120 kv line in the vicinity
of Oregon Mountain, California.
Tennessee Valley Authority, March 10, 1967
The failure of a current transformer at the Bowling Green, Kentucky, substation resulted in a 50,000
kilowatt interruption for 18 minutes to the City
of Bowling Green and the Warren County Rural
Electric Cooperative Cooperation.
Moreau (
12,1967
Icing cc
terruption
of 2,000 k
Eagle Bu
South Dal
restored i!
Western
1967
More t!
area, inch
Aluminun
Bureau o
interrupte
ville Pow
to Belling
lators. Pr
Sedro WC
loaded an
1 line op
Columbia
surge whc
the Canal
which car
Oregon 1
der, in U
Sacramer
1967
During
off in th
Pacific G
lines sup1
MUD. S
50,000 b
minutes.
Grand R
Servic
em near
for nine
failed on
Sherrard
Insula
of servic
area aro
kilowattr
Moreau Grand Electric Cooperative, Inc., March
12,1967
Marquette Board of Light and Power, March 26,
1967
Icing conditions on 69 kv lines resulted in an interruption of service to 2,200 customers with a load
of 2,000 kilowatts in the area around Timber Lake,
Eagle Butte, Dupree, Isabel, and McLaughlin,
South Dakota. Lines were sectionalized and service
restored in one hour and 13 minutes.
The entire 10,500 kilowatt load and 8,500 customers of Marquette, Michigan, system was lost for 50
minutes when a broken insulator caused tripping of
a new generating station.
Western United States and Canada, March 14,
1967
More than 50,000 customers over a widespread
area, including the 256,000 kilowatt load of Intalco
Aluminum at Bellingham, Washington, and the
Bureau of Standards at Denver, Colorado, were
interrupted for as much as 24 minutes after Bonneville Power Administration opened its Snohomish
to Bellingham 230-kv line to replace damaged insulators. Puget Sound Power & Light Company’s
Sedro Wolley-Beverly Park No. 2 line became overloaded and was opened manually. The parallel No.
1 line opened by relay. Two 230-kv lines to British
Columbia either overloaded or were tripped by a
surge when Puget’s lines were reclosed. The loss of
the Canadian lines created a 480,000 kilowatt surge
which caused tripping of tie lines at the CaliforniaOregon boundary, at the Arizona-California border, in Utah, and across Colorado.
Sacramento Municipal Utility District, March 16,
1967
During high winds, a jumper connection burned
off in the Brighton, California, substation of the
Pacific Gas & Electric Company, tripping the two
lines supplying the Hedge substation of Sacramento
MUD. Service was lost to 37,748 customers and
50,000 kilowatts in Sacramento County for 23
minutes.
Grand River Dam Authority, March 19,1967
Service was interrupted to two industrial customers near Choteau Generating Plant in Oklahoma
for nine hours and 25 minutes when a cross arm
failed on a 115 kv line and set the pole on fire.
Sherrard Power System, March 19,1967
Insulator contamination caused an interruption
of service.to 5,000 customers in a 500 square mile
area around Orion, Illinois. The load was 10,300
kilowatts.
Pacific Power @ Light Company, March 26, 1967
A 69 kv line fault interrupted service for six
hours and 32 minutes to 2,500 customers with a
load of 5,000 kilowatts in the Enterprise and Elgin,
Oregon, areas. Insulators on sections of the line
owned by both Pacific Power & Light Company and
California Pacific Utilities had beendamaged by
gun fire.
Tennessee Valley Authority, March 27, 1967
A bird caused an arc across an insulator at the
Mayfidd substation, apparently severing a line conductor. Service was interrupted to 25,000 customers
in Mayfield, Kentucky, and surrounding areas for
59 minutes. Total load lost was 52,000 kilowatts.
Georgia Power Company, March 27,1967
Both Atkinson-Marietta 115 kv lines were open at
Marietta for work on the lines. This upset relay coordination. When a 115 kv jumper connection
burned off at a clamp in the Marietta substation,
23,800 kilowatts in the area were interrupted for
14 minutes, 2,376 kilowatts were interrupted for
two hours and 2,380 kilowatts were out for 50
minutes.
Puget Sound Power t3 Light Company, March 28,
1967
One of two 115 kv underground circuits to Mercer Island (East Seattle) was taken out of service
in connection with the relocation of a 230 kv line.
The load on the remaining circuit was interrupted
when the underground cable or a pothead failed.
About 22,000 customers with a load of 45,000 kilowatts were without power for 27 minutes.
Utah Power B Light Company, March 28, 1967
A cooling water leak spraying on a transformer
and a circuit breaker caused the breaker to trip.
The trouble was not correctly identified and the
equipment was returned to service in 11 minutes,
only to trip out again. The second outage was for
9 minutes. The 35,000 kilowatt loss affected some
8,400 customers in Grand, Carbon, San Juan, and
. .
3
. . TT. -1Emery counties in eastern and soutneastern uran.
Bangor Hydro-Electric Company, April 12, 1967
South Carolina Electric and Gas Company,
A loose connection caused a flashover on two 46
kv insulators on the main bus at the Graham generating station which resulted in loss of power to
about 42,000 customers with a load of about 35,000
kilowatts in Bangor, Brewer, Veazie, Orono, Stillwater, Orrington, Hampden, East Corinth, LaGrange, and Milo, Maine. Service was completely
restored in 27 minutes.
8,1967
Service to some 15,000 customers amounting to
38,000 kilowatts in Charleston, South Carolina, was
interrupted for 23 minutes when a tree fell on a
115 kv line.
Jefferson Davis Electric Coop, Inc., April 13, 1967
Insulation contamination caused an interruption
of service to some 2,000 customers amounting to
about 6,000 kw in Cameron Parish, Louisiana, for
3 hours and 23 minutes.
Muscatine, Iowa Municipal Electric Plant, April
IS,1967
The system’s entire load of approximately 27,000
kilowatts and 8,000 customers was interrupted for
approximately two and one-half hours after high
winds felled a large tree across a 69 kv line near
the system’s 56,000 kilowatt generating plant.
Bailey County Electric Coop. Association, April 19,
1967
Failure of an insulator on a 69 kv line resulted in
the loss of 9,000 kilowatts of load in Bailey County,
Texas, for one hour.
Western United States and Canada, April 20, 1967
Failure of BPA’s Snohomish-Bellingham 230 kv
line during the installation of a transfer trip relay
caused numerous transmission lines to trip in Washington, Idaho, and Montana. About 800,000 kilowatts of load in the Bellingham, Washington, area
and about 210,000 kilowatts of load in southern
Idaho were interrupted for a few minutes. The
east-west transmission ties in Montana and Nebraska did not trip during the initial disturbance
but tripped eleven minutes later as a result of heavy
flows to the west.
Community Public Service Company, May I, 1967
High winds and lightning caused a 138 kv line to
trip and result in loss of service for one hour to 3,140
customers in Collin and Fannin County, Texas.
Carolina Power & Light Company, May 1, 1967
25,000 kilowatts of load in the city of Rocky
Mount, North Carolina, was interrupted for about
an hour when the 110 kv bus at the Rocky Mount
substation tripped. Cause of the interruption is
unknown.
192
May
Gulf States Utilities Company, May 11, 1967
An interruption of 696,000 kilowatts affecting
163,000 customers occurred in an area of southeast
Texas. Loss of service ranged from 45 minutes to
about seven hours. The interruption was caused by
failure of a 138 kv lightning arrestor and a high side
bushing on a 500 mva transformer at Sabine generating station. Clearing of this fault caused loss of
a 440,000 kilowatt unit. About five minutes later,
failure of a wave trap caused tripping of two 138
kv lines and resulted in complete collapse of the
Company’s Texas load.
Virginia Electric tY Power Company, May 12,1967
The failure of a lightning arrestor on a 115 kv
line resulted in an interruption of service to 12,500
customers with a load of 38,000 kilowatts in Richmond, Virginia, for 24 minutes.
City of Greenville, Texas, May 12, 1967
Failure of a static exciter on the municipal system’s steam-electric station caused loss of 17,000
kilowatts of load for about two and one-half hours.
Cleveland Electric Illuminating Company, May 17,
1967
Service to 66,000 customers with a load of 80,000
kilowatts was interrupted for 27 minutes when four
132 kv transformer bank circuit breakers were manually tripped at the Clinton Substation. Company
reported that barbed wire barriers across the top of
the main gate to the substation had been cut.
South Texas Electric Cooperative, Inc., May 19,
1967
Operation of a 69 kv bus differential relay at the
Sam Rayburn generating station separated the dation from its load. Service was interrupted to 17,135
customers and 14,600 kilowatts for 24 minutes.
Bonneville Power Administration, May 25, 1967
Damage to BPA’s Bell-Metaline Falls 115 kv line
in the Spokane, Washington area at 7: 39 P.M.,
PDT, resulted in the interruption for as much as one
hour and sixteen minutes of approximately 31,000
kw to several thousand customers of the Pend Oreille
PUD and Washington Water Power Company sys-
terns. The
ing plane
cident.
Cincinnati
Failure
ure of a p
station of
in control
to some L
kilowatts i
tucky, for
to over sin
tinued to
de-energiz
and to in
downtowr
Snohomis
Approx
watts of lc
a brush fi
kv line SI
County nc
Pennsylva
tion, June
At abo
tripped a
Company
erations j
terns. The line damage was caused by a crop dusting plane which was damaged slightly in the accident.
Cincinnati Gas & Electric Company, May 26, 1967
Failure of a 13 kv cable and the subsequent failure of a pothead on a voltage regulator in the substation of the West End generating station and fire
in control cables in the station interrupted service
to some 40,000 customers with a load of 48,000
kilowatts in Cincinnati, Ohio, and Covington, Kentucky, for periods of time ranging from 30 minutes
to over six hours. The fire in the control cables continued to the next day when it was necessary to
de-energize all incoming circuits to the substation
and to interrupt service to 6,500 customers in the
downtown area of Cincinnati.
Snohomish County PUD, June 2,1967
Approximately 15,000 customers and 32,000 kilowatts of load were interrupted for 29 minutes when
a brush fire burned a pole and crossarm on a 115
kv line serving the northern part of Snohomish
County near Everett, Washington.
Pennsyluania-New Jersey-Maryland Interconnection, June 5,1967
At about 10: 16 A.M., EDT, excessive loading
tripped a 220 kv line on the Philadelphia Electric
Company’s system which in turn caused other operations from instability or overloads until power
service was lost in a 15,000 square mile area covering parts of Pennsylvania, New Jersey, Maryland,
and Delaware. Estimates indicated that approximately 13,000,000 people and 1 O,OOO,OOO kilowatts
of load were affected. Although about a dozen generating units suffered varying amounts of damage
during the disturbance, service was gradually restored to all areas within about ten hours. A detailed
resume of this interruption is included in Chapter
3 of the main report.
Utah Power and Light Company, June 9, 1967
At 6 : 48 P.M., MST, trouble outside of the Utah
Power and Light Company system resulted in the
tripping of a 46 kv line to Gadsby Steam Electric
Plant and a 130 kv line serving the Salt Lake City
distribution system. Approximately 105,000 kilowatts of load was interrupted for one minute and
50,000 kilowatts for 15 minutes.
Pennsylvania Power and Light Company, June 12,
1967
Approximately 78,000 customers and 163,000
kilowatts of load in Lycoming and Schuylkill Counties in Pennsylvania were interrupted at 2 : 01 P.M.,
EDT, when a 220 kv lightning arrester failed on a
220/66 kv transformer bank at Frackville Substation. The failure occurred during clear weather and
the cause was unknown. Service was restored to 113
mw within 15 minutes and to the remaining 50 mw
within 24 minutes.
193
T ABLE E-l .-Rlmml of power intmu@ons 1954-1966
Approximate Location
Date
Probable Cause
Oicge
.1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
4:
4
4;
4f
41
5f
51
5:
5:
9
5:
5t
5’
194
L-30-54
3-30-54
9-54
&lo-54
&15-54
>30-54
2-19-54
3-55
3-55
j-25-55
6-55
7- 7-55
8-55
8-55
lo-55
6-56
9-28-56
Q-18-56
Z-14-56
I- 3-57
l-23-57
l-27-57
l-57
3-57
4- 9-57
5-20-57
5-23-57
6-l 7-57
6-27-57
8- 2-57
o-31-57
3-20-58
6- 4-58
6-18-58
6-17-58
?- 2-58
?- 2-58
9-58
12-58
l- 2-59
l- 7-59
1-15-59
l-29-59
8-17-5:3
12-28-5! 3
l- ?-6f 1
3- l-6( 1
3- 2-6( 1
4-28-6t I
5- 54 1
5-23-6t 1
6-29-6t 1
9- !3-6( 3
9-l l-6(3
3- 3-6 1
6-13-6 1
6-21-6 1
C Ileveland, Ohio . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E astern Massachusetts. . . . . . . . . . . . . . . . . . . . . . .
Nlortheast Coast. . . . . . . . . . . . . . . . . . . . . . . . . . . .
CChicago, Ill. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E ast coast. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CCleveland, Ohio. . . . . . . . . . . . . . . . . . . . . . . . . . . .
C hicago,Ill................................
Peoria,Ill..................................
11 ndiana, Ohio, Pennsylvania. . . . . . . . . . . . . . . . . .
s ummit, N.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C llney,Tex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
N lew York, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E,ast coast. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
K lew England Coast. . . . . . . . . . . . . . . . . . . . . . . . .
lx lortheast U.S. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
s tephensville, Wii. . . . . . . . . . . . . . . . . . . . . . . . . . .
T ‘oledo,Ohio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B lew York, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C:onnccticut, N. J . . . . . . . . . . . . . . . . . . . . . . . . . . . .
P‘lattsburg, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
P ‘eru, Ind. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Little Rock, Ark. . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 ‘enncssee, Kentucky, West Virginia. . . . . . . . . .
Ii Kansas, Colorado, Texas, Oklahoma, New Mexico
I Dallas, Tex. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I!Kansas-Missouri . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Elast Aurora, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . .
PTew York, N.Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I ouisiana-Texas . . . . . . . . . . . . . . . . . . . . . . . . . . . .
bYashington, D.C. . . . . . . . . . . . . . . . . . . . . . . . . . .
nvlinneapolis, Minn. . . . . . . . . . . . . . . . . . . . . . . . . .
Pgortheast Coast . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
sit. Paul, Minn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ISldorado, Kans. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I,ouisiana-Mississippi. . . . . . . . . . . . . . . . . . . . . . . .
I<earney,N.J . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
(Charleston, S.C . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
rrTorth Carolina. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
tUbuquerque, N. Mex. . . . . . . . . . . . . . . . . . . . . .
ESeattle, Wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 jan Antonio, Tex. . . . . . . . . . . . . . . . . . . . . . . . . . .
Ikrgen, N.J. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
:k. Louis, MO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
rNew York, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Western New York . . . . . . . . . . . . . . . . . . . . . . . . .
Orange,N.J . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tennessee, Alabama, Georgia. . . . . . . . . . . . . . . .
Texas, Louisiana. . . . . . . . . . . . . . . . . . . . . . . . . . .
Oklahoma City, Okla . . . . . . . . . . . . . . . . . . . . . . .
Oklahoma. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hilo, Hawaii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cleveland, Ohio. . . . . . . . . . . . . . . . . . . . . . . . . . .
East Coast. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Long Island, N.Y . . . . . . . . . . . . . . . . . . . . . . . . . .
Norwalk,Conn . . . . . . . . . . . . . . . . . . . . . . . . . . . .
San Francisco, Calif. . . . . . . . . . . . . . . . . . . . . . . .
Southern Idaho. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Major Short Circuit.
Hurricane Carol.
Hurricane Edna.
Flood.
Hurricane Hazel.
snow Storm.
Turbine Explosion
Transformer Failure.
Storm.
Lightning.
Weather Balloon Drifted Onto Line.
Dverload of Distribution Feeders.
Hurricane Connie.
Hurricane Diane.
Floods.
Wind Storm.
He Line Breaker Misoperation.
Transformer Tap Changer Failure.
ice Storm.
Distribution Feeder and Transformer Failure.
Flood.
Ice Storm.
Floods.
Blizzard.
Tornado.
Tornado.
Wind Storm.
Curtailment.
Hurricane Audrey.
Underground Cable Failure.
Lightning Arrestor Failure.
Blizzard.
Tornado.
Tornado.
Operating Error.
Distribution Transformer Failure.
Gas Line Fire.
Hurricane Helene.
Snow Storm.
Substation Fire.
Substation Breaker Failure.
Power Plant Failure.
Ice Storm.
Underground Cable Failures.
Sleet.
Fire.
Ice Storm.
Ice Storm.
Tornado.
Tornadoes.
Tidal Wave.
Underground Cable Failure.
Hurricane Donna.
Hurricane Donna.
Substation Equipment Explosion.
Circuit Breaker Explosion.
Fire.
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
8C
81
82
81
84
8:
8t
8:
81
8:
90
91
92
93
94
95
96
97
98
99
108
101
102
103
104
105
106
107
108
109
110
111
TABLE
hrtage
No.
Date
E-l.-Rlsuml of power interruptions 1954-I966-Continued
Approximate Location
Probable Cause
-
.-
58
59
60
6-29-61
7- 3-61
7-13-61
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
8-4-61
8-29-6 1
9-l 1-61
9-21-61
1 1-13-61
3-l 3-62
3-62
6-25-62
8- 5-62
8-l 3-62
8-20-62
8-20-62
O-l 2-62
O-12-62
.o-12-62
.2-30-62
3-17-63
7-23-63
6-13-63
6-19-63
6-28-63
12- - 6 3
2-24-64
3- 4-64
3-10-64
4-3-64
4- 3-64
4- - 6 4
5-23-64
8-10-64
91
92
93
94
95
96
97
98
99
lot
101
102
103
104
105
8-27-64
8-27-64
9-9-64
lo- ‘i-64
11-19-64
1 l-30-64
12- 4-64
12- 5-64
12-22-64
l- 7-65
l-23-65
l-28-65
2-17-6:
4- 7-6:
4-l 1-6:
1Ot
105
1Of
101
ll(
111
4-16-6:
4-27X
4-29-6:
5-18-6!
6-16-6:
6-27-6:
iouthernIdaho . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power Plant Failure.
Transmission Line Failure.
kouthern Idaho . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Bushing Failures in Adjacent Distribl ution Feeder
Jew York, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Breakers.
Transmission Line Flashover.
Cleveland, Ohio. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rain and Lightning.
Nassau, N.Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
&.lveston, Tex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hurricane Carla.
,ong Island, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . .
Hurricane Esther.
ZlPaso,Tex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Snow Storm.
Xendale, Calif. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating Error.
Atlantic City, N.J. . . . . . . . . . . . . . . . . . . . . . . . . . .
Storm.
Operating Error.
owa-Nebraska. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Underground Cable Failure.
jtaten Island, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . .
‘asadena, Calif. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Failure of Four Oil Filled Cutouts.
3rooklyn, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Underground Cable FailureXeveland, Ohio. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tornado.
?ortland,Oreg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . storm.
Nashington-Oregon . . . . . . . . . . . . . . . . . . . . . . . . . S t o r m .
3ellingham, Wash. . . . . . . . . . . . . . . . . . . . . . . . . . . S t o r m .
Storm and Wind.
Vassau,N.Y . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Circuit Breaker Control Circuit Failure.
I’ampa, Fla . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Failure of Plant Circulating Water Pump.
Blackwell, Okla. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Failure of Transmission Line Splice.
Cansas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
YVestchester, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . .
Hot Weather.
Staten Island, N.Y. . . . . . . . . . . . . . . . . . . . . . . . .
Hot Weather.
Dam Failure.
Los Angeles, Calii. . . . . . . . . . . . . . . . . . . . . . . . . .
rexas-Oklahoma. . . . . . . . . . . . . . . . . . . . . . . . . . .
Exciter Flashed Over.
jouthwest Tennessee . . . . . . . . . . . . . . . . . . . . . . .
Tornado.
Rain and Sleet.
Kingston, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Earthquake.
Alaska . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tidal Wave.
California-Oregon. . . . . . . . . . . . . . . . . . . . . . . . . .
Frog in Relay.
Jacksonville, Fla. . . . . . . . . . . . . . . . . . . . . . . . . . .
Transmission Line Fault.
Long Island, N.Y. . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Regulator Closed on Fuel Supply Line to
Sweetwater, Tex. . . . . . . . . . . . . . . . . . . . . . . . . . .
Large Power Plant.
Emergency Shutdown of a 13 mw unit.
Lordsburg, N. Mex . . . . . . . . . . . . . . . . . . . . . . . . .
Miami,Fla. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hurricane Cleo.
North Florida. . . . . . . . . . . . . . . . . . . . . . . . . . . . . H u r r i c a n e D o r a .
Louisiana. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hurricane Hilda.
Submarine Cable Failure.
Northwest Washington. . . . . . . . . . . . . . . . . . . . .
Teaneck,N.J . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Circuit Breaker Failed to Operate.
Eastern N.Y.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Ice Storm.
Michigan City, Ind . . . . . . . . . . . . . . . . . . . . . . . . . Line Short.
Northern California. . . . . . . . . . . . . . . . . . . . . . . . F l o o d s .
Western Pennsylvania . . . . . . . . . . . . . . . . . . . . . . . Boiler Tube Failure.
Chicago, Ill. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I c e S t o r m s .
Iowa-Nebraska . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Operating Error.
Lawrenceburg, Ind. . . . . . . . . . . . . . . . . . . . . . . . . . Operating Error.
Minneapolis, Minn. . . . . . . . . . . . . . . . . . . . . . . . . . Tornadoes.
Iowa, Illinois, Indiana, Wisconsin, Michigan 1, Tornadoes.
Ohio.
Bird Nest Fell on Power Line.
Chester, Pa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Operating Error.
Arizona . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Earthquake.
Tacoma,Wash . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Mud Slide on Powerhouse.
Lower Baker, Wash . . . . . . . . . . . . . . . . . . . . . . . . .
Floods.
Denver, Colo. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
. -.-. .
DesMeines,Iowa . . . . . . . . . . . . . . . . . . . . . . . . . .
TABLE
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
196
E-l .-Rhmc’
of
power interruptions 19%1966-Continued
Date
Approximate Location
8-29-65
9-9-65
s9-65
ll- 9-65
1 l-22-65
12- 2-65
12- 6-65
l-24-66
l-28-66
3- 3-66
4-26-66
5-13e
5-16-66
6- 7-66
6-8-66
7- 3-66
7- 7-66
7-l l-66
7-l l-66
7-19-66
7-12-66
7-13-66
7-14-66
7-26-66
7-27-66
7-26 &
27-66
8-29-66
ll- 3-66
ll- 5-66
1 l-10-66
1 l-14-66
1 l-22-66
1 l-24-66
12- 2-66
12-14-66
12-19-66
12-23-66
Des Moines, Iowa. . . . . . . . . . . . . . .
Louisiana. . . . . . . . . . . . . . . . . . . . . . .
Florida. . . . . . . . . . . . . . . . . . . . . . . .
Northeast U.S . . . . . . . . . . . . . . . . . .
Elgin, Ill . . . . . . . . . . . . . . . . . . . . . . . .
Texas-New Mexico. . . . . . . . . . . . . .
Beaumont, Tex. . . . . . . . . . . . . . . .
Los Angeles, Calif. . . . . . . . . . . . . . . .
Dallas, Tex . . . . . . . . . . . . . . . . . . . . . .
Jackson, Miss. . . . . . . . . . . . .
...
western u.s . . . . . . . . . . . . . . . . . . . . .
Anchorage, Alaska. . . . . . . . . . . . .
Columbus, Ga. . . . . . . . . . . . . . . . . .
Western U.S . . . . . . . . . . :. . . . . . . .
Clearwater, Fla. . . . . . . . . . . . . . . .
Fairfax, Va. . . . . . . . . . . . . . .
. .
Nashville, Tenn. . . . . . . . . . . . . . .
...
Nebraska . . . . . . . . . . . . . . . . ...................
St. Louis, M O . . . . . . . . . . . . ...................
Los Angeles, Calif. . . . . . . . ...................
Washington-Idaho. . . . . . . . ...................
Tulsa, Okla. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Houston, Tex. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ElPaso,Tex . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Oregon,Calii . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Travis Ail Base, Calii. . . . . . . . . . . . . . . . . . . . . . . . .
.. .
..
Farmington, N. Mex. . . .
Southern Virginia. . . . . . . . .
..
Atlanta, Ga. . . . . . . . . . . .
..
.
Oakland, Calif. . . . . . . . .
..
..
LasVegas,Nev.. . . . . . . . . . . .
..
..
..
.
Chicago, Ill. . . . . . . . . . . .
..
..
Seattle, Wash. . . . . . . . . .
..
Southeastern Missouri. . . . .
Austin, Tex. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sandy Spring, Ga. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Jonesboro, Ark. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Probable Cause
Lightning.
Hurricane Betsy.
Hurricane Betsy.
Undesired Relay Operation.
Wind.
Loss of Fuel Supply.
Misoperation of Supervisory (Control).
Operating Error.
Ice and Wind.
Tornado.
Erroneous Telemeter Signal.
Pranksters.
Tornado.
False Relaying of 345 KV Circuit.
Hurricane Alma.
Transformer Failure.
Winds.
Faulty Relay Setting.
Curtailment.
Breaker Operations-Cause Unknown.
Lightning.
Car Hit Pole.
Transformer Failure.
Lightning and Wind.
Line Failure and Breaker Operations.
Line Flashover During Maintenance.
Breaker Bushing Failure.
Rain Storm.
Breaker Failure.
Vandalism During Strike.
Breaker Bushing Failure.
Generator Oil Pressure Failure.
Transformer Relay Operation-Cause Unknown.
Fault on Secondary System.
Tree Felled on Line.
Lines Tripped Out-Cause Unknown.
Sabotage of Control Circuits.
Galloping Conductors.
POWER INTERRUPTIONS
1954 - 1966
FI~IJRE E - l
.“.S. GOVERNMENT PRlNTlNG OFFICE: 1967
O-267-781